EFFECT OF ALCOHOL AND TOBACCO UPON THE EYES.
I must not close without warning my hearers against the baneful effects of alcohol and tobacco upon the eyes. It is not uncommon for the eye surgeon to meet with persons who have become partially blind from the effects of these poisons upon their optic nerves. Of course, only a small proportion of those who use alcohol and tobacco to excess are affected in this way, but this renders it none the less certain that impaired sight is one of the dangers that we may avoid by abstaining from the use of these unnecessary and poisonous luxuries.
TUMORS OF THE BLADDER.
DIAGNOSED BY MEANS OF THE ELECTRO-ENDOSCOPIC CYSTOSCOPE.
By Dr. Max Nitze.
In the following lines I wish to direct the attention of my English confreres to the value of the electro-endoscopic mode of examination of the male urinary bladder, invented by me. I believe I could not have chosen a more suitable theme for that purpose than a short report of the bladder tumors diagnosed by me cystoscopically; for the diagnosis of these new formations offers the greatest difficulty, and in most cases it has been impossible till now to prove their existence with accuracy without digital exploration of the bladder. By the new method of cystoscopical examination the conditions have entirely changed. One look into the bladder, illuminated as if by daylight, is generally sufficient to afford means for forming an opinion of all the questions coming into consideration—viz., size, form, and site of the tumor. The accompanying diagrams (Figs. 1, 2, 3, 4) may give an idea of the appearances which the different forms of bladder tumors present endoscopically. I regret that they cannot show the brightness of the light by which one sees the tumors during examination. The celebrated Vienna specialist, V. Dittel, is right in saying that "they offer sometimes truly charming pictures;" especially certain kinds of villous tumors, whose long slender villi floating in the liquid often present a splendid appearance. The following are the cases cystoscopically diagnosed by me.
Fig. 1.
Case 1.—A man, aged fifty-five, under the care of Dr. Ch. Mayer, suffered from attacks of hæmaturia for thirty years. During the last six years he has had dysuria and inability to empty the bladder completely. The patient had been examined by the sound repeatedly by eminent surgeons and specialists, but none could give a certain diagnosis. On Nov. 11, 1886, I undertook the cystoscopic examination. I found on the anterior wall of the bladder a puffy swelling covered with white masses of mucus. (See Fig. 1.) The trigone was covered by a mass consisting of pointed papillæ. On account of the weakness of the patient extirpation was impossible. The patient became weaker
and weaker, and died in June, 1887. The post mortem examination showed the internal orifice of the urethra surrounded by a swelling representing a continuous tumor as large as a small apple. It was found that the instrument had penetrated through the middle of this swelling, which bled easily on pressure. In spite of this, the clearness of the picture was not interfered with in the least.
Fig. 2.
Case 2.—A man, aged fifty, was obliged to exert a strong pressure in order to empty the bladder. The flow of urine often stopped. He himself introduced a catheter, and on withdrawing it a piece of villous tissue was found. On Dec. 10, 1886, I saw, on cystoscopical examination, directly and immediately over the internal orifice of the urethra, a villous swelling hanging from the anterior wall of the bladder. (See Fig. 2.) On Jan. 15, 1887, extirpation of the tumor by means of the high section was performed by Professor v. Bergmann. The size of the tumor (which was as large as a pigeon's egg) and its position corresponded exactly to the endoscopic picture. The patient recovered.
Fig. 3.
Case 3.—A patient under the care of Professor Madelung, aged fifty-five, suffered from attacks of hæmaturia. Examination by sound and rectal palpation had given me negative results. On Feb. 20, 1887, cystoscopical examination was made. On the left side of the trigone a tumor with a broad base was seen, which resembled somewhat a strawberry in size and form. (See Fig. 3.) On March 1, Professor Madelung undertook the extirpation of the tumor. The appearance corresponded exactly to the cystoscopic picture. The patient recovered.
Fig. 4.
Case 4.—This was a patient on whom Dr. Israel had performed the high section a long time before, on account of a bladder tumor. The extent was so great that only its most prominent part could be removed. The microscopical examination proved the diagnosis of cancer. Quick healing took place. The patient became free from pain, and the urine became clear. In
order to see what had become of the remaining part, the cystoscopical examination was undertaken on April 3. It was easy to see that the right lateral wall was covered to an extent of from three to four centimeters with thick masses of verrucous and fungiform excrescences. (See Fig. 4.)
[We omit the description of the additional cases.]
The above shortly described fifteen[9] cases of bladder tumors have been diagnosed by me cystoscopically during the last sixteen months. This is a proof, on the one hand, of the value of the cystoscopic examination; on the other hand, of the fact that the new formations in question are not of so rare occurrence as has been hitherto thought. I would like to emphasize that the important results were often obtained under the most difficult circumstances. In several cases the external orifice of the urethra was found abnormally small; in others (Cases 8 and 11) the examination was made during the occurrence of a continuous hemorrhage from the tumor; in one case (Case 1) I introduced the instrument through the center of the tumor, which bled on the slightest pressure. In spite of this the appearances were seen satisfactorily. In the first case a post mortem examination was made; in eight other cases (Cases 2, 3, 9, 10, 11, 13, 14, and 15) the tumor was extirpated, seven times by the high section—in one case, that of a woman, through the dilated urethra. In these nine cases the endoscopic appearances were in every important respect confirmed in the most perfect manner. In every case my opinion regarding the size, position, and form was found to be correct. It is only in those cases where the edges of the tumor overlap the short pedicle that the latter cannot be observed. Besides, the relative good results of the operations undertaken on account of the cystoscopic appearance may be emphasized. Of the eight patients from whom the tumors had been extirpated, none died from the result of the operation. Case 9 proved fatal on account of the progressive extension of the growth. In the eleventh case there was a recurrence, but the patient is still alive. Five patients (Cases 2, 3, 10, 13, 14) must be considered entirely cured. Case 15 is still under treatment, and, as the conditions of the patient are at present (ninth day after operation) in every way satisfactory, a complete recovery is anticipated.
[9] The first eight cases are more fully described in the Arch. fur Chirurgie, vol. xxxvi., Part 3 (Dr. Nitze, Beitrage zur Endoscopie der mannlichen Harnblase). The full account of the last seven cases will be published soon.
Finally, on comparing the above cystoscopic appearances with the results obtained by other methods of examination, it must be observed that the examination of the urine, in most cases carefully made, had only in two cases shown the presence of villous tissue, which in one instance was brought out by the catheter. The rectal palpation, when made, had always given negative results. Further, the examination by means of the sound had been made in nine cases before the cystoscopic examination. In none of the cases had the sound revealed the presence of a tumor (which in two had attained the size of a small apple), although the examination was made by most experienced surgeons and eminent specialists. Those cases show how imperfect an instrument the sound is for the diagnosis of bladder tumors.
Only one method can compare with the cystoscope in giving valuable information regarding the size and nature of a bladder tumor—viz., the digital exploration of the internal surface of the bladder after a previous boutonniere, or the high section. The superiority of the cystoscopic method over the latter, on account of the smaller amount of inconvenience it causes the patient, need not be insisted on. The latter involves a cutting operation not free from danger, as well as deep narcosis, while the cystoscopic method is similar to a simple catheterization.
Fig. 5.
The accompanying diagram (Fig. 5) shows the instrument used by me for cystoscopic examination. It has been made by the Berlin instrument maker, Hartwig, according to my instructions. The source of the light (Mignon lamp) is cemented in a silver capsule, which is screwed into the distal end of the cystoscope. This instrument is superior to that made by Leiter, the Vienna instrument maker, because of its greater simplicity in construction, which allows the lamp to be easily replaced when necessary, and also on account of the greater length of the shaft.
I mention this because it differs from the explanation
which Mr. Fenwick gave in his speech concerning my method of examination at the meeting of the Medical Society of London on Jan. 23, 1888. I must also strongly contradict Mr. Fenwick's statements concerning the share which he attributed to the Vienna instrument maker in the construction of the instrument. Leiter's connection with our instrument will be best explained when I say that he had to buy the patent[10] from me first in order to be allowed to make the instrument. Leiter has had no share in those peculiarities which characterize it as new. The introduction of the source of light into the organ had been practically brought about, the optical apparatus enlarging the view designed, the whole construction perfected, the instrument had proved itself useful in examining patients, and had been demonstrated by me in the Saechsisches Landes Medicinal Collegium before Leiter had any idea of the new invention! Also the eventual replacement of the first source of light (platinum wire) had been provided for.[11] Leiter has only made a few technical modifications on the finished instrument. I protest most emphatically against the incorrect explanations given by Mr. Fenwick, and against every connection of Leiter's name with my instruments. I hope to obtain in England the same generous recognition of my labors in this field that has been accorded to me in Germany.—Lancet.
[10] Deutsche Patentschrifte, No. 6, 853.
[11] Ibid.
PAPILLOMATOUS TUMOR OF THE BLADDER, DEMONSTRATED BY MEANS OF LISTER'S ELECTRO-CYSTOSCOPE.
By F. N. Otis, M.D., Clinical Professor, College of Physicians and Surgeons, New York.
A. G——, aged twenty-three, United States; single; barber.
The young man was referred to me by his former medical attendant, March 16, 1883. His urine was found to be slightly but distinctly tinged with blood, and contained some small clots as well as some pus and mucus. He complained of exquisite pain on urination, increased at the close, recurring every half hour. Through examination per rectum (a posteriori) unusual tenderness was found. Distinct increase in the density and thickness of the right inferior section of the bladder was recognized by the bimanual touch; a catheter was introduced, and three ounces of bloody urine removed. The bladder was then irrigated gently with a saturated solution of boric acid until the fluid returned clear. The catheter was then withdrawn, leaving about four ounces of the solution, of a temperature of 80°, in the bladder, as a preparation for its examination by the electro-cystoscope of Lister. The required current was furnished by the small six-cell battery of the Galvano-Faradic Co. The cystoscope was then introduced into the bladder, and the current turned on. The illumination was complete. Through the slightly rosy medium the small blood vessels in the bladder mucous membrane were distinctly seen. On the right side a deep red, granular-looking mass, with a wavy outline, was then distinctly observed, covering about one-fourth of the cystoscopic field. This appearance was verified by Drs. Abbe, Bangs, and W. K. Otis—the unanimous opinion being that it represented a papillomatous growth, to some extent covered by coagulated blood. Two days later a similar examination was made, under the influence of an anæsthetic, which corroborated the previous observations in every particular. (See illustration.)
DIAGRAM OF BLADDER, SHOWING LOCATION OF TUMOR AND POSITION OF CYSTOSCOPE.
Some small filaments were subsequently removed with the lithotrite, but on microscopical examination nothing of diagnostic importance was discovered. From lack of the capacity of the bladder, the field was necessarily limited, nevertheless, a very excellent view of the tumor could be obtained. This is shown in the illustration, from a sketch made at the time of the first examination. It represents the position of the tumor and cystoscope when the best view of it was obtained.
On the following Monday the patient entered St. Luke's Hospital, and was operated upon by my associate, Dr. L. B. Bangs, Dr. Charles McBurney assisting. The high operation was performed, and the bladder being examined by means of an electric light, introduced through the suprapubic incision, the diagnosis made by the cystoscope was verified in every particular. The growth was then removed, as far as possible, with the scissors, and the surface cauterized with the Paquelin cautery. At the present writing the patient is going on toward a satisfactory recovery. The pathological examination made by Dr. Frank Ferguson, pathologist of St. Luke's Hospital, showed the neoplasm to be a simple papilloma.
This case is deserving of especial interest as being the first tumor of the bladder diagnosticated in this country by means of the cystoscope, and verified by subsequent
operation, and adds one more to the list of sixteen cases so made out by foreign observers, and two by Dr. Fenwick, of England. In this instance the instrument deserves particular credit, as other methods had completely failed in the practice of competent observers.
This consists of a metal tube, about seven inches long, of a caliber of 22 French, having at the proximal end a funnel shaped ocular opening; at the distal, a short beak, similar to that of the catheter coudé. A window of rock crystal is set in the end of this beak, behind which a small electric lamp, controlled by a switch at the ocular end, is placed. A rectangular prism, the hypothenuse plane of which is silvered, is placed in the end of the straight portion of the tube, its superior face being seen just anterior to the angle formed by the beak. The distended bladder is illuminated by the electric lamp, the rays reflected from its wall falling on the prism experience total reflection, an inverted image being formed within the tube. The size of the field thus obtained is greatly increased by means of a telescope introduced into the tube. The image seen through the cystoscope is an inverted image, but right and left are not transposed.
THE CYSTOSCOPE.
There can be no question as to the great prospective value of the electro-cystoscope in diagnosis of many difficulties to which the bladder is subject. A variety of foreign bodies have already been reported as made out by use of this instrument. The locality, size, and color of vesical calculi have been demonstrated in my own experience. In one instance two stones were seen where only one had been previously found, but this of course might with care have been effected by means of the lithotrite. But it is in the diagnosis of the tumors, and encysted or impacted calculi, that the most essential service may be anticipated from the use of the cystoscope. The orifices of the ureters are quite readily brought into the cystoscopic field, and it is more than probable that (perhaps through the introduction of some clear fluid with which blood does not readily mingle—glycerine, for instance) the true source of a previously doubtful hæmaturia will be demonstrated.—Medical Record.
DISTANCE AND CONSTITUTION OF THE SUN.
So many queries about the solar system, or the members of it, have come recently to the attention of those in charge of this journal, from various sources, that it is thought best to make a brief statement of the present state of knowledge that astronomy has of the solar neighborhood in which we live.
Naturally we begin with the sun, and the oldest and most important problem which the study of this body offers is the determination of its distance from the earth in terrestrial units of measure. This distance is important because the knowledge of all the phenomena of all the heavenly bodies, except those of the moon, depend directly or indirectly on its value. The problem of the sun's distance is difficult because the data given for determining it are insufficient to enable the astronomer to apply the principles of trigonometry directly to it. He is, therefore, compelled to use indirect methods of solution, which, at best, give only approximations to the true distance, arising chiefly from small errors in observation, which, at the present time, seem unavoidable. A familiar illustration will make our meaning clear. The knowledge we have of the sun's distance depends on the accurate measurement of a small angle formed by drawing two lines from a point at the sun to the extremities of the earth's radius. That angle is called the sun's parallax. Ptolemy thought that this angle was 3′ of arc, but we now know that its value is very near 8.80" of arc, and that the error of this amount from the true angle probably is not more than 0.02". To measure this small angle has been the astronomer's great trouble since the time of Aristarchus, and he does not yet know its value accurately. His problem is like that of a surveyor attempting to measure a ball, whose real diameter is one foot, at the distance of 4.4 miles nearly; and unless he can determine the diameter of the ball so that he shall not be uncertain in his measure to the amount of 0.03 of an inch, his work will not add anything useful to present knowledge.
If we suppose the angle of parallax to be known, the computation of the distance of a celestial body is easy. Multiply earth's radius by 206,265 (seconds of arc in the unit radius), and divide the product by the angle of parallax in seconds of arc. The mean equatorial radius of the earth, as given in Clark's Geodesy, is 3963.3 English miles. The sun's distance for a parallax of 8.78" would be
206,265" × 3963.3
————————————————— = 93,108,000 miles.
8.78"
For parallax of 8.80" = 92,897,000 miles.
For parallax of 8.82" = 92,686,000 miles.
The range of error in parallax, as here given, is 0.04", and the change of the distance of the sun in allowing for this error is nearly half a million of miles. If 8.80" be the assumed parallax, with ± 0.02" as probable error, then the uncertainty of the sun's distance is still nearly a quarter of a million of miles.
So far astronomers are pretty generally agreed, unless it be in the value of the earth's radius used above. In his excellent work, entitled "The Sun," we notice that Professor Young gives 3,962.72 English miles as the "latest and most reliable determination" (page 22), while he seems to use Bessel's value of 3,962.80 in obtaining 92,885,000. This may be because the last named value is still in most general use, though less accurate undoubtedly than that of Clarke.
Since the transit of Venus, of 1874, the determination of the solar parallax has not been very much improved.
The transit of 1882, so far as known, has given surprisingly discordant results, and probably they will be of very little service in improving our knowledge of the distance of the sun. In the midst of all this uncertainty of late work, in ordinary methods two ways of studying the problem show results almost exactly alike. They are obtained from late improved measures of the velocity of light, and from measures by the heliometer. The parallax from these sources is 8.794". The Brazilian results of transit of Venus for 1882, by Wolf and Andre, recently published, make the parallax 8.808". The American reductions for the last transit are not yet completed.
From the above brief statement of results, it seems that the value of the solar parallax is likely to be a trifle under 8.80", rather than above it, making the distance of the sun probably very near 93,000,000 miles.
The next most important problem pertaining to the sun is its constitution, which is usually considered under four heads:
1. The central portion, thought to be made up chiefly of intensely heated gases.
2. That part which is seen by the aid of the telescope, called the photosphere, consisting of a "shell of luminous clouds formed by the cooling and condensation of the condensible vapors at the surface where exposed to the cold of outer space." (Young.)
3. Outside of the photosphere is a shallow stratum, called the chromosphere, "composed mainly of uncondensible gases (conspicuously hydrogen) left behind by the formation of the photospheric clouds, and bearing something the same relation to them that the oxygen and nitrogen of our own atmosphere do to our own clouds." (Young.) And—
4. The corona, which is the beautiful halo seen, with the naked eye, outside of all, during the time of a total eclipse of the sun. This curious halo with all its streamers and rifts is thought to be composed chiefly of an incandescent material, in a far more attenuated state than that of hydrogen, the rarest gas known, because it yields freely in the spectroscope a certain line, 1474 K, which most agree can mean nothing else, although no one knows what the gas or metallic vapor is. Hydrogen is also found in the corona extending to the height of 600,000 miles above the photosphere, and possibly 1,200,000 miles. Suspended in this mixture of vapors, and "falling into, or projected from, the sun is a large quantity of solid or liquid material, which is at such a temperature as to be self-luminous. It is this which yields the continuous spectrum, free from dark lines.
"Besides these components in the outer envelope, there is present matter which reflects or diffuses light much as our own atmosphere does.
"To this is attributed the partial radial polarization of the corona. The streamers and rifts indicate matter repelled, in various quantities, from the sun by forces which may be electrical." (Hastings.)
These are the views advanced by astronomers and physicists, as theories or working hypotheses, until something better or more certain can be known. They are not held as facts by any, because of insufficient proof to establish them as such, and because there are very grave objections to some of them which are at present unanswerable.
For example, the spectroscope shows that the gaseous pressure at the limit of the chromosphere is very small, although that is at the base of an atmosphere from 600,000 to 1,200,000 miles deep, and under the influence of a force of gravity more than twenty-seven times as great as that in action at the surface of the earth.
Optically, the atmosphere of the earth ceases at a height of forty-five miles, but bodies at twice that altitude, moving at the rate of twenty-seven miles per second, meet resistance of air enough to render them incandescent almost instantly. But the evidence seems clear that, far within the corona, the resistance to moving bodies is much less than in our atmosphere at a height of sixty miles. The great comet of 1882 passed through the coronal atmosphere within 300,000 miles of the sun, with a velocity one hundred and eighty times that of the earth in its orbit. The comet was not stopped, nor destroyed, nor its orbit disturbed, as subsequent observations showed. The same thing was true, so far as known, of the comet of 1843, which passed still nearer the solar surface. These facts are troublesome to explain on the hypothesis of a coronal atmosphere.
Still further: if the sun be surrounded by a gaseous envelope, its density, as aforesaid, ought to diminish from the solar surface outward to its upper limits; but the fact is, the material of 1474 K line always appears in the spectrum of chromosphere, which would seem to indicate, by its place, that it is as much more dense than hydrogen as is magnesium vapor, or even the vapor of iron. But the evidence of the spectroscope makes this 1474 K material far less dense than that of hydrogen, and this is a contradiction that is very troublesome to the student of solar physics.
In studying the polarization of the light of the corona, it is clear that the amount of polarized light reflected from a particle at the surface of the sun is nothing, "because the luminous source there is a surface with an angular subtense of 180°;" hence polarization of the corona near the limb of the moon ought to be small, farther away, larger. But observation shows that the contrary is true, i. e., the percent. of polarized light increases as the corona is observed nearer the limb of the moon during totality.
These are a few of the difficult questions that stand in the way of accepting the foregoing theories as facts pertaining to, or well grounded knowledge of, the constitution of the sun. They are by no means all, or possibly the most important ones. They are certainly among those that are receiving very general attention at the hands of physicists at the present time.—Sidereal Messenger.
CHANGES IN THE STELLAR HEAVENS.
By J. E. Gore, F.R.A.S., Honorary Associate and Vice-President of the Liverpool Astronomical Society.
If we look up at the starry heavens on a clear, moonless night, all seems still, lifeless, and devoid of energy and motion. All of us are—or at least should be—familiar with the apparent diurnal motion of the star sphere, caused by the actual rotation of the earth on its axis, and with the slower annual motion, due to the earth's revolution round the sun, which brings different constellations into view at different seasons of the year. These motions, due to the great and universal law of gravitation, discovered and so ably expounded by the famous Sir Isaac Newton, are of course wonderful and orderly in their regularity, and bear silent testimony to the amazing power, majesty, and goodness of a great and glorious Creator. There are, however, other motions and changes, even still more wonderful, going on in the depths of space, which, though unperceived by the ordinary observer, have been revealed to the eye and contemplation of the astronomer by the accurate instruments and methods of research which modern science has placed at his disposal. Some accounts of these marvelous discoveries may prove of interest to the reader. The "fixed stars" are so called because they apparently hold a fixed position with reference to each other on the concave surface of the celestial vault, and do not, as far as the unaided eye can judge, change their relative positions as the planets do. Many stars have, however, what is technically called a "proper motion," which, though of course very minute, and only to be detected by the aid of refined and accurate instruments, yet accumulate in the course of ages, and sensibly alter their position in the sky. The largest "proper motion" hitherto detected (about seven seconds of arc per annum) is that of a small star in the constellation Ursa Major, known to astronomers as No. 1830 of Groonbridge's catalogue. It has been calculated that this star is rushing through space with the amazing and almost inconceivable velocity of 200 miles per second!—a velocity which would carry it from the earth to the sun in about 5½ days and to the moon in 20 minutes! The well-known double star 61 Cygni has a proper motion of about five seconds of arc per annum, both components moving through space together. This is, as far as yet known, the nearest star to the earth in the northern hemisphere. Its parallax, as determined by Sir R. S. Ball, is 0.4676 of a second of arc, and by Prof. Pritchard (by photography) 0.43 of a second. Taking the mean of these values, its distance from the earth would be about 460,000 times the earth's mean distance from the sun, and its actual velocity about 33 miles per second. This is, of course, the motion at right angles to the line of sight, but as it may also have a motion in the line of sight, either to or from the eye, its real velocity is probably greater than this. The remarkable triple star 40 Eridani has a proper motion of four seconds annually. The components are a fourth magnitude star accompanied by a distant double companion which is a binary (or revolving double star), and accompanies the bright star in its flight through space. There are two other faint and distant companions which do not partake in the motion of the ternary star. In the year 1864 the bright star was situated to the east of a line joining these faint companions, but owing to its large proper motion it is now to the west of them. In the case of the triple star Struve 1516, one of the companions, which was to the west of the primary star in 1831, is, owing to the proper motion of the bright star, now to the east of it. Prof. Asaph Hall has found a parallax for 40 Eridani of 0.223 of a second. This, combined with the observed proper motion, indicates an actual velocity of about 54 miles per second. The star Mu Cassiopeiæ has also a large proper motion. This star, about 4,000 years ago, must have been close to Alpha Cassiopeiæ, and might have been so seen by the ancient astronomers. The proper motion of the bright star Arcturus is so considerable that in the course of about 30,000 years it will be near the equator, and about 10° to the north of the bright star Spica, from which it is at present separated by over 30°. These motions are of course those which take place across the face of the sky. There are, however, motions in the line of sight—both toward and from the eye—which have of late years been revealed to us by the spectroscope, that wonderful instrument of modern scientific research, by the aid of which several new metals have been discovered, and which has been found so useful in chemical analysis, and even in the manufacture of steel by the Bessemer process. Some years since, Dr. Huggins, the eminent spectroscopist, found that the bright star Sirius, "the monarch of the skies," was receding from the earth at the rate of about 20 miles a second. Later observations at Greenwich Observatory showed that this motion was gradually diminishing, and within the last few years it has been found that the motion of recession has been actually changed into a motion of approach, showing that this giant sun is probably traveling in a mighty orbit round some as yet unknown center of gravity.
From a consideration of stellar proper motions, it has been concluded that the sun—and therefore the whole solar system—is moving through space. Recent investigations make the velocity of translation about 19 miles per second (30 kilometers). The Greenwich observations place the "apex of the solar motion" (as the point toward which the sun is moving is called) between Rho and Sigma Cygni, while Dr. Huggins' results fix a point near Beta Cephei. Both these points are near the Milky Way.
There are other startling changes which have occasionally taken place among the stars, and which must be looked upon almost in the light of catastrophes. At rare intervals in the history of astronomy "temporary" or "new" stars have suddenly blazed out in the heavens which were previously either unknown to astronomers, or else were invisible, except in the telescope. Some of these were of great brilliancy. In A.D. 173 a bright star is recorded in the Chinese annals as having appeared between Alpha and Beta Centauri (two bright stars in the southern hemisphere). It remained visible for seven or eight months, and is described as resembling "a large bamboo mat" (!)—a not very lucid description. It is worthy of remark that there exists at the present time, close to the spot indicated, an interesting variable star, which may possibly be identical with the bright star of the
second century. Perhaps the most remarkable of these wonderful objects was that observed by the famous Tycho Brahe in 1572, in Cassiopeia, and called the "Pilgrim." It was so brilliant that it rivaled the planet Venus at its brightest, and was visible at noonday. It remained visible for over a year and then disappeared.
A small star close to its recorded position has been observed in recent years, and as it is thought to be slightly variable in its light, it may possibly be identical with the long lost star of Tycho Brahe. Another new star of almost equal brilliancy was observed in October, 1604, in Ophiuchus, a few degrees southeast of the star Eta Ophiuchi. The planets Mars, Jupiter, and Saturn were close together in this vicinity, and one evening Mostlin, a pupil of Kepler's, remarked that a new and very brilliant star had joined the group. When first seen it was white, and exceeded in brightness Mars and Jupiter, and was even thought to rival Venus in splendor! It gradually diminished, however, and in six months was not equal in luster to Saturn; in March, 1606, it had entirely disappeared. In 1670 a star of the third magnitude was observed by Anthelm near Beta Cygni. It remained visible for about two years, and increased and diminished several times before it finally disappeared. Flamsteed's star, No. 11 of Vulpecula, has been supposed to be identical with Anthelm's star, but Baily could not find that such a star exists. A small star has, however, been observed at Greenwich within one minute of arc of the place assigned to the temporary star by Picard's observations.
Variability has been suspected in this faint star, and according to Hind it has a hazy, ill-defined appearance about it, which may perhaps suggest that it may be a small planetary nebula, similar to Schmidt's new star of 1876 in Cygnus. A small new star was observed by Hind in Ophiuchus on April 28, 1848. When first noticed it was about the fifth magnitude. It afterward rose to about fourth magnitude, but very soon faded away, and, although still visible in the telescope, has become very faint in recent years. A new star of seventh magnitude was found by Pogson on May 28, 1860, in the well-known star cluster known as 80 Messier in Scorpio. The light of the star when first seen obscured the light of the nebula. On June 10 the star had nearly disappeared, and the nebula was again seen shining with great brilliancy.
A very interesting temporary star—known as the "Blaze Star"—suddenly appeared in Corona Borealis in May, 1866. It was first seen by the late Mr. Birmingham, of Tuam, Ireland, on the night of May 12, when it was of the second magnitude and equal in brightness to Alphecca, the brightest star in the well-known "Coronet." It must have made its appearance very suddenly, for Dr. Schmidt, the director of the Athens observatory, stated that he was observing this region of the heavens a few hours previously, and noticed nothing unusual. It rapidly diminished in brightness, and on May 24 of the same year was reduced to nearly the ninth magnitude. It was soon discovered that the star had been previously observed, and its place registered by the great German astronomer, Argelander, as of magnitude 9½, so that it is possibly a variable star of irregular period and fitful variability. When near its maximum brilliancy, its light was examined by Dr. Huggins with the spectroscope, which showed the bright lines of incandescent hydrogen gas in addition to the ordinary stellar spectrum. This implies that the great increase in its light was due to a sudden outburst of hydrogen in the star's atmosphere. Some observers remarked that when viewed with the naked eye it decidedly twinkled more than other stars in the neighborhood, which rendered a correct estimate of its relative brightness somewhat difficult. During the years 1866 to 1876, Schmidt detected variations of light which seemed to show a period of about 94 days, and these observations were confirmed by Schonfeld.
On the evening of November 24, 1876, the late Dr. Schmidt, of Athens, discovered a new star of the third magnitude, near Rho Cygni, in a spot where he was certain that no bright star was visible four nights previously. When first seen, it was somewhat brighter than Eta Pegasi. It did not, however, remain long at this degree of brightness, but rapidly decreased, and on November 30 had faded to fifth magnitude. It afterward diminished very regularly, and in September, 1885, was estimated only fifteenth magnitude with the 15½ inch refractor of Mr. Wigglesworth's observatory. The star was examined with the spectroscope a few days after its discovery, and showed bright lines similar to the "Blaze Star" in the Northern Crown. One of these bright lines was believed to be identical with Kirchhoff's No. 1474, which has been observed in the spectrum of the solar corona during total eclipses of the sun. This star would seem to be quite new, as there is no star in any of the catalogues in its position. In September, 1877, it was examined with the spectroscope at Lord Crawford's observatory, and its light was found to be almost entirely monochromatic (of only one color), showing that the star "had changed into a planetary nebula of small angular diameter" (!)
In August, 1885, a star of about seventh magnitude made its appearance close to the nucleus of the Great Nebula in Andromeda—a well-known object visible to the naked eye, and which has been well called "the Queen of the Nebulæ." The new star was independently discovered by several observers toward the end of August, but seems to have been first certainly seen by Mr. T. W. Ward, of Belfast, on August 19, at 11 P.M. At Greenwich observatory the spectrum of the new star was found "of precisely the same character as that of the nebula, i. e., it was perfectly continuous, no lines, either bright or dark, being visible, and the red end was wanting." Dr. Huggins, however, on September 9, thought he could see from three to five bright lines in its spectrum. The star gradually faded away, and on February 7, 1886, was estimated only sixteenth magnitude in the 26 inch refractor of the naval observatory at Washington. From a series of measures by Prof. Asaph Hall he found "no certain indications of any parallax," so that evidently the star and the nebula, in which it probably lies, are situated at an immense distance from the earth. Prof. Seeliger has investigated the decrease in light of the star on the hypothesis that it was a cooling body, which had been suddenly raised to an intense heat by the shock of a collision, and finds a fair agreement between theory and observation. Anwers points out the similarity between this outburst and the new star of 1860 in the
cluster 80 Messier, and thinks it very probable that both phenomena were due to physical changes in the nebulæ in which they occurred.
With reference to the colors of the stars, some of the red stars have been suspected to vary in color. The bright star Sirius is supposed—from the description of it by ancient astronomers—to have been originally red, but this seems very doubtful. The Persian astronomer Al Sufi, in his "Description of the Heavens," written in the tenth century, describes the well-known variable star Algol distinctly as a red star. It is now white, and this is perhaps the best attested instance on record of change of color in a bright star.—Naturalists' Monthly.
THE COMMON DANDELION.
By Frederick Leroy Sargent.
In the various names which the dandelion has received, we see expressed, for the most part, either a reference to the tooth-like recurved lobes of the leaves, Fig. 1, or an allusion to the medicinal properties of the plant. Thus, our English name is a modified form of the French dent de lion, meaning lion's tooth, and in German we have the same idea expressed in Löwenzahn. Fifty years ago this plant appeared in the botanies as Leontodon taraxicum, the generic name being derived from the Greek leon, lion, and odons, tooth, and the specific from the Greek tarasso, to stir up, in reference to the effect of a dose. In later works we find the genus Leontodon, including the "fall dandelion" (L. autumnale), but not the true dandelion, which now appears in a genus by itself under the name Taraxicum Densleonis. Here the specific name is merely "lion's tooth" again, in Latin.
Fig. 1.
Finally, in the latest works our plant is given as Taraxicum officinale, since this has been found to be the name which, according to the rules of botanical nomenclature, takes precedence of all others. An allusion to the teeth is thus no longer retained, the only reference remaining being to the plant's officinal use.
To the majority of people the mention of the dandelion calls to mind not so much its medicinal properties as its use for food. Although its cultivation, either as a spring pot herb or as a salad with blanched leaves, is comparatively modern, the wild plant seems to have been long valued as a vegetable. There is reason to believe that the Romans made use of it as a pot herb, and Chinese writers of the fourteenth century mention its being eaten in their country, although there is no evidence of cultivation at that time.
There are but few of our flowering plants that grow so widespread over the world. It occurs in North America from the Atlantic to the Pacific coast, in Europe, in Asia, and in the Arctic regions. This extensive range may in part be accounted for by the fact that our plant belongs to the large and aggressive family of the Compositæ, and is thus related to such invaders as daisies, burdocks, and thistles. Still, the dandelion has more to recommend it than mere family connection; for, despite its lowly aspect, it is no poor relation, but, as we shall hope to show in the present article, it has many virtues of its own which entitle it to respect.
Prominent among these is its adaptability to the different conditions under which it grows. It seems to make the best of everything. If by chance a seed falls upon poor, thin soil, the young plant sends forth, as rapidly as possible, a rosette of leaves pressed close to the earth. And thus, on the principle that "possession is nine points of the law," it secures for its roots the use of a certain amount of territory quite safe from the encroachments of other plants. In rich ground the case is quite different, for here there is so much nutriment in a small quantity of earth, that the struggle for soil is not such a life and death matter as in the less favored localities. Consequently we find a large number of plants crowded together as close as they can stand; and it is obvious that if, under these circumstances, the dandelion should develop a flat rosette of leaves, the grass and other plants growing around would soon overshadow it, and it would have small chance for life.
Our plant, therefore, extends its leaves upward, and does its best to elongate them so as to keep pace with the growth of its rivals. But as these are for the most part grasses and plants which grow by elongation of the stem, the race for sunshine is rather in favor of these other plants, for the reason that a given amount of material put into a stem makes a stiffer organ than when put into a leaf. Still, even with these odds against it, the dandelion seems well able to hold its own, for it probably derives more or less advantage from the recurved lobes, or teeth, which give the plant its name. These are admirably fitted to act in much the same manner as a ratchet; and when the neighboring grasses are blown against the dandelion, a blade may slide along the margin of the leaf toward the base; but, as it springs back from its own elasticity, it cannot slide in the opposite direction, for a tooth will catch it, and thus force it to help support the leaf, and hold it up to the sunshine. We need not stop to consider how the dandelion behaves in soil which is neither very rich nor very poor, for enough has been said to show that it has not much to fear from any rivals it may meet under ordinary circumstances.
It is not only against the aggressions of neighboring plants, however, that our dandelion needs to be prepared.
It is at least equally important for its welfare that it have some means of protection against herbivorous animals—not only such as might eat its leaves, but also the more stealthy ones that live upon the food which plants store underground. All such foes it thwarts by a means as simple as it is efficient. Every part of the plant contains a milky juice which is intensely bitter, and a first taste is quite enough to convince the most stupid animal that raw dandelion is not good eating, and most animals know enough to let it severely alone. Curiously enough, however, in this, as in many other cases, it happens that what in nature acts to deter animals from eating the plant, with man offers the chief attraction, for it is this very bitter principle (taraxacin) which gives to dandelion greens their peculiar flavor, and affords the essential element in the extract which physicians prescribe.
The store of food, referred to above, which the dandelion accumulates in its root, not infrequently enables it to pass, almost unharmed, through dangers that with less provident plants would surely prove fatal. For example, it must often happen that from drought or from being trampled upon by animals, the leaves become wholly or in part destroyed. Now, if there were no reserve store of food, the plant would have no chance of rallying; but as it is, this food supplies the material for new growth, and upon the return of favorable conditions, fresh leaves are developed, and the plant lives on as before. Primarily, of course, the purpose of this storage of food is to enable the plant to live on from year to year, resting in the winter, and in the spring beginning work again with a good start.
In comparing the higher with the lower plants, the superiority of the former is most beautifully shown in the better provision which is made for the welfare of offspring; and in this regard our dandelion stands among the highest. Before we can understand the ways in which our little plant performs this part of its life work, we must briefly consider the structure of the blossom.
Fig. 2.
If with a sharp knife we cut a blossom in halves, from the stem upward, the parts represented in Fig. 2 will be disclosed. Surmounting the stalk is a cushion-like receptacle, R, from the top of which arise a number of tiny flowers, F, while from the side grow out a series of green scales, S, forming an involucre around the whole. A single one of these florets, Fig. 3, exhibits the following parts: First, a bright yellow corolla, C O, tubular below, but strap-shaped above, as if a tube had been split for part of the way on one side, and the upper part flattened. Second, five stamens, S K, attached by slender filaments, F M, to the tubular part of the corolla, and with their anthers or pollen sacs, A N, joined together by the edges to form a tube. Third, a single pistil having a long style, S Y, which, above, passes through the anther tube, and bears at its end two diverging stigmas, S G, and below connects by a short neck, N, with the small ovary, O, which contains a solitary ovule. Fourth, a calyx, C X, composed of numerous slender bristles.
Fig. 3.
The purpose of these complex structures is, of course, in one way or another to secure the development of the ovule into a seed fitted to produce a new plant. This development will proceed only after the ovule has been influenced (i. e., fertilized) by pollen placed upon the stigma; but when once the mysterious process of fertilization has taken place, then there follows immediately those wonderful changes in the blossom which culminate in the ripening of the fruit.
There are but two possible ways in which fertilization may be secured; either the pollen which affects the ovule must come from the same flower (then called close fertilization), or the pollen must come from another flower of the same kind (cross fertilization). Now, while either of these methods will insure the production of a seed, numerous experiments go to show that those offspring which result from cross fertilization are in many ways superior to those which are produced from close fertilization; and it is to the advantages of cross fertilization that we have to look for an explanation of the significance of many peculiar structures, not only of the dandelion, but of flowers in general.
It is obvious that, to secure cross fertilization, there must be some agent to transfer the pollen from one plant to another. Most commonly, either the wind is taken advantage of for this purpose, as with elms, pines, grasses, etc., or else flying insects are induced to perform the office, as is the case with the majority of our familiar flowers. The wind is a very wasteful carrier,
so that for every grain that is properly placed, thousands, or even millions, may be lost. Insects, on the contrary, waste but little; and, moreover, as Aristotle so shrewdly observed, they habitually confine their visits, for a number of trips, exclusively to the flowers of one species.
The dandelion seems to fully appreciate the great advantages of securing the services of insects, for it appeals most strongly to their love of bright colors and their passion for sweets. As the flowers open, each tiny golden cup is filled to the brim with purest nectar, and he must be a very dull insect, indeed, that cannot see the brilliant head of flowers as far as he can see anything. At any rate, it is not the dandelion's fault if he does not, for the blossom is placed where it will be as conspicuous as possible. If the surrounding herbage is tall, the flower stalk is elongated, so that the crown of flowers may not be obscured. If the plants around are low-lying, it would be wasteful to have a long stalk, so it has a short one, sometimes so short that the blossom looks like a button in the center of the leaf rosette. Economy of material is furthermore shown in the fact that the stalk is always hollow, for it is a principle well known to builders that, when there is required a pillar of a given strength, less material is needed for the tubular form than for the solid cylinder.
Fig. 4.
Fig. 5.
But to return to our flower. We have next to consider how the visits of insects are utilized to secure cross fertilization. If we examine the anther tube of a flower that has just opened, Fig. 4, we shall see that the style has not yet protruded, but fills the entire cavity, except such space as is occupied by a quantity of pollen which the anthers have shed. So much of the style as is within the tube is thickly beset with hairs that point upward; and when the lower portion elongates, this hairy part brushes the pollen out of the tube, and protrudes, covered with the yellow dust, Fig. 5. At this stage, an insect coming for nectar must rub against the style, and so become more or less covered with pollen. None of it, however, can get upon the stigmas, for they are not yet exposed. After a short time has elapsed, during which much of the pollen has probably been rubbed off, the style is seen to split at the top; and as the halves separate and roll back, Fig. 3, their inner faces (the stigmas) are exposed. If, now, the flower be visited by an insect which has previously been to a younger flower, the pollen he brings will be deposited upon the stigmas as he rubs against them, and cross fertilization will be effected.
Let us suppose, however, that no insect visits the blossom—and this must often happen to such as appear very early in the spring or late in the fall, when hardly any insects are around. In such cases we find that seeds are produced, and therefore we must infer that fertilization has in some way or other been secured. An examination of a flower still older than any we have considered, Fig. 6, will show us what takes place. Here it will be seen that, after the stigmas have diverged, they continue to roll back, until a coil of one or more turns has been made; and as a result of this the stigmatic surface comes in contact with the hairs on the style, and touches the pollen grains entangled by them. Still, the close fertilization thus accomplished is only a last resort, and it can only occur in the event of insects' visits having failed; for when pollen from another flower has once fallen on the stigma, no pollen coming afterward can have the least effect. Thus, we have another instance of the dandelion's ability to make the best of its surroundings.
Fig. 6.
It even adapts itself to the weather; for when the sun shines, the scales of the involucre bend back, and the blossom is expanded to its fullest extent; but in dull weather, or at night, the scales bend inward, and the blossom is tightly closed. The advantages of this remarkable movement, with its implied sensitiveness, is obvious when we consider that insects are abroad only in sunshine, while at other times there is danger of dew or rain getting into the nectar, and so spoiling it for the insects.
After fertilization has been accomplished throughout the blossom, the involucre closes, and remains closed during the ripening of the fruit. The changes which now take place are as follows: In each flower the corolla, stamens, and style, being of no further use, wither, and sever their connection with the ovary; the ovule develops into a seed containing a tiny plantlet well provided with food for its use during germination;
the ovary grows to keep pace with the seed, its tissues become hardened, and a number of spine-like projections develop near the upper part; and finally the short neck which bears the calyx bristles elongates, pushing upward the withered parts of the flower. At this stage the involucral scales bend back through an arc of about 180°, the cushion-like receptacle becomes almost spherically convex, the fruits radiate in all directions, the bristles spread, and a beautiful cluster of little parachutes is presented to the wind.
Fig. 7.
Fig. 8.
Even a glance at one of these fruits, Fig. 7, is sufficient to discover a wonderful fitness for transportation by wind, and more careful study shows that this fitness pervades every detail. For example, on examining the bristles microscopically, Fig. 8, it is shown that they are not simple threads, but each is hollow and has numerous projections extending on either side, all of which serves to increase the buoyancy in a very effective way.
The experience of aeronauts has shown that a highly important part in the equipment of a balloon, after the attainment of buoyancy, is the provision of some means of arresting the balloon's progress when the destination has been reached. One of the most successful means which they employ is the grappling hook; and as we find the base of our diminutive parachute provided with a number of upwardly directed spines, it seems fair to conclude that these serve to arrest the fruit upon favorable soil. If it comes to rest upon a smooth surface—which, of course, would be barren—the next breeze would easily blow it away; but if it chance to fall on soil or among other plants, the effect of the spines would be to retain it against the power of even a strong wind. Thus, we may leave it safely landed upon good soil, ready to begin under favorable conditions the cycle of its wonderful life.—Popular Science News.
SYSTEMATIC RELATIONS OF PLATYPSYLLUS, AS DETERMINED BY THE LARVA.[12]
By Dr. C. V. Riley.
There is always a great deal of interest attaching to organisms which are unique in character and which systematists find difficulty in placing in any of their schemes of classification. A number of instances will occur to every working naturalist, and I need only refer to Limulus, and the extensive literature devoted, during the past decade, to the discussion of its true position, as a marked and well-known illustration. In hexapods the common earwig and flea are familiar illustrations. These osculant or aberrant forms occur most among parasitic groups, as the Stylopidæ, Hippoboscidæ, Pulicidæ, Mallophaga, etc. Probably no hexapod, however, has more interested entomologists than Platypsyllus castoris Ritsema, a parasite of the beaver. I cannot better illustrate the diversity of opinion respecting its true position in zoology than by giving an epitome of the more important literature upon it.
[12] Read at the meeting of the National Academy of Sciences, April 20, 1888.
J. Ritsema, in Petites Nouvelles Entomologiques for September 15, 1869, described the species as Platypsyllus castoris. He found it on some American beavers (Castor canadensis) in the zoological garden of Rotterdam. He considered it to "undoubtedly" belong to the Suctoria of De Geer, and to form a new genus of Pulicidæ.
In the same year, in the Tijdschrift voor Entomologie, 2d ser., vol. v., p. 185 (which I have not seen), the same author publishes what is apparently a redescription of the insect. He gives his views more fully as to its systematic position, considering that it belongs to the Aphaniptera, and is equivalent to the Pulicidæ.
In the same year, Prof. J. O. Westwood (having previously read a description of the species, November 9, 1868, before the Ashmolean Society of Oxford) published in the Entomologist's Monthly Magazine, vol. vi., October, 1869, pp. 118-119, a full characterization of the insect under the name of Platypsyllus castorinus. A new order, Achreioptera, is established upon the species, which he very aptly likens, in general appearance, to a cross between a flattened flea and a diminutive cockroach. "The abnormal economy of the insect, its remarkable structure, the apparent want of mandibles, our ignorance of its transformations, and the possibility that the creature may be homomorphous in the larva and pupa states," are the reasons assigned for establishing the new order, and here Prof. Westwood is perfectly consistent, as in his famous "Introduction to the Classification of Insects" the Forficulidæ are placed in the order Euplexoptera; the Thripidæ in the order Thysanoptera; the Phryganeidæ in the order Thrichoptera; the Stylopidæ in the order Strepsiptera; and the Pulicidæ in the order Aphaniptera.
In 1872, Dr. J. L. Le Conte published his paper "On Platypsyllidæ, a New Family of Coleoptera" (Proc. Zool. Soc. of London for 1872, pp. 779-804, pl. lxviii.), in which he shows that Platypsylla is undoubtedly coleopterous and cannot possibly be referred to the Aphaniptera. Careful descriptions and figures of anatomical details are given, and he finds that its affinities are very composite, but in the direction of the Adephagous and Clavicorn series. Its most convenient place is
shown to be between the Hydrophilidæ and Leptinidæ. There seems to be no good reason why the name Platypsyllus is here changed to Platypsylla, a spelling adopted by most subsequent American writers.
In 1874, Prof. Westwood, in the "Thesaurus Entomologicus Oxoniensis" (Oxford, 1874), p. 194, pl. xxxvii., gives figures with details; reprints his previous diagnosis, and maintains his previous course in erecting a new order for the insect, without giving any additional reasons.
In 1880, P. Megnin, in "Les Parasites et les maladies parasitaires," etc., Paris, 1880, gives (pp. 66-67) a description of the family "Platypsyllines" without expressing an opinion concerning the systematic position. He also describes and figures the species.
In 1882, Dr. Geo. H. Horn (Trans. Amer. Ent. Soc., x., 1882-83; Monthly Proc., Feb. 10, 1882, p. ii.) exhibited drawings illustrating the anatomy of Platypsylla and Leptinus, and showed that a close relationship exists between these genera. Later, in his "Notes on Some Little Known Genera and Species of Coleoptera" (Trans. Amer. Ent. Soc., x., 1882-83, pp. 113-126, pl. v., 114-116), he reviews the characters, and explains and illustrates the anatomical details. The differences he points out between his observations and those of Le Conte are more particularly in the mandibles. In connection with this paper he also describes and illustrates the structure of Leptinillus, which he separates from Leptinus, and demonstrates their close relationship with Platypsyllus.
In 1883, Le Conte and Horn, in their "Classification of the Coleoptera of North America" (Washington, Smithsonian Institution, 1883), give (pp. 13-15) a full description of the family characters, a little modified from Le Conte's first description, but sustaining his views on the systematic position of Platypsyllidæ.
In 1883, Alphonse Bonhoure (Ann. Soc. de France, 1883; Bull, des Seances, p. cxxvi.) exhibited drawings and specimens of Platypsyllus castoris found in the Departement des Bouches du Rhone.
In 1884, Edm. Reitter, in "Platypsylla castoris Rits. als Vertreter einer neuer europaischen Coleopteren-Familie" (Wiener entom. Zeit. iii., 1884, pp. 19-21) gives a lengthy description of the species with special regard to the sexual differences. He shows that the European insect is not specifically distinct from the American form, but he does not express an opinion on the position of the family among the Coleoptera.
In the same year, Bonhoure (Ann. Soc. Ent. de France, 1884, pp. 143-153) more fully records its discovery on Castor fiber taken in the Petit-Rhone. It is a question whether this European beaver, now quite rare, is distinct from ours. He gives a very good review of the subject, with a plate of the most important details, after Horn, and he fully indorses the coleopterological position of the insect.
In the same year Ritsema (Tijdschrift voor Entomologie, 1883-84, lxxxvi.) refers to Bonhoure's discovery of Platypsylla in France, and corrects Reitter in some unimportant details.
In 1885, Reitter, in "Coleopterologische Notizen" xiii. (Wiener entomolog. Zeit., vol. iv., 1885, p. 274), answers Ritsema's criticism.
In the same year, Dr. Friederich Brauer, in his masterly "Systematisch-zoologische Studien" (Sitzh. der Kais. Akad. der Wissensch., xci., p. 364), speaks of the relationship in the thoracic characters between Mallophaga and Coleoptera as illustrated by Platypsyllus, by inference admitting the coleopterous nature of the latter, but recognizing that it has mallophagous affinities.
In 1886, H. J. Kolbe, in his "Ueber die Stellung von Platypsyllus im System" (Berlin entom. Zeitsch., xxx., 1886, pp. 103-105), discusses the subject, without any new evidence, however. He concludes that most of its characteristics relate it to the Corrodentia, and particularly to the sub-order Mallophaga, in which it has its closest kinship in Liotheidæ. The remarkable tripartite mentum he thinks should not be compared with the bipartite mentum of Leptinus, and calls attention to the fact that in Ancistrona in Mallophaga it is also trilobed.
The above are the more important papers on the subject, though the insect has been referred by other authors to both Neuroptera and Orthoptera.