SECTION IV.—Part V.—Insecta (Coleoptera, Diptera, Hemiptera, Aphaniptera).

Whilst very many flies, bugs, lice, and fleas persecute animals, not a few of them also attack man. Several of the species are genuine parasites, others are semi-parasitic, and others, again, are altogether outside the border-land of parasitism in the ordinary sense of the term. In fact, it becomes difficult to say where the line of parasitism should be drawn. I cannot, however, ignore all notice of the insect tormentors, whether strictly parasitic or not.

At least fifty different species have been regarded as playing the rôle of parasitism in man. Amongst the Coleopterous parasites none is more authentic than Blaps mortisaga. At least half a dozen such cases have occurred. Mr Hope’s catalogue of insects producing parasitism in man gives three examples of scolechiasis from this source. Sir J. R. Cormack published a fourth case, and I have recorded a fifth. In this instance I received the living larva from Dr Horne, of Barnsley, who procured it from an infant eleven weeks old. In my ‘Introductory Treatise’ I have alluded to the case of the girl Riordan, who not only passed per anum upwards of 1200 larvæ, but also several perfect insects. The case was first reported by Pickells, Thomson, and Bellingham. One of the other authentic cases, in which only a few larvæ were present, was recorded by Patterson, of Belfast, and the third case by Bateman. Mr Hope’s ‘Catalogue’ originally appeared in the ‘Transactions of the Entomological Society,’ being afterwards published in the pages of the ‘London Medical Gazette,’ 1837. Patterson’s case was also, I believe, first communicated to the Entomological Society.

As regards the mode in which the maggot gained access to the child in Horne’s case, it was not easy to decide; but in the case of the girl Riordan the mode of ingress was sufficiently explained. The Blapsidæ, as a family, are closely allied to the meal-worms, and, like most of the Tenebrionidæ, are black and foul-smelling beetles, frequenting dark and damp situations, from which they escape only at night. The family comprises numerous species, of which probably not more than three are found in this country. They are abundant in Africa, especially in Egypt, where (according to Fabricius, as quoted by Westwood, Figuer, and others) the women eat Blaps sulcata cooked with butter in order to make themselves grow fat. The insects are also employed as specifics against ear-ache and the bite of the scorpion. The superstitious notion of a “charm” is generally at the bottom of these domestic remedies. In the girl Riordan’s case, as Westwood observes (when epitomising Pickell’s account), the parasites, as such, “probably originated in an absurd and superstitious practice, which she had for some time followed, of drinking daily for a certain time a quantity of water mixed with clay, taken from the graves of two Catholic priests, and eating large pieces of chalk. One of these beetles was immersed repeatedly in spirits of wine, but revived after remaining therein all night, and afterwards lived three years.” The intolerance of light shown by the perfect insect seems to be equally shared by the larva. Of this fact I had repeated evidence by observing the behaviour of the living specimen sent to me by Dr Horne. Thus, when, on February 5th, 1877, I placed the maggot on the surface of some moist mould, scarcely half a minute elapsed before it commenced to bore its way downwards, and in less than a minute all but the tip of the tail had disappeared. In like manner, when, on the 7th, I raised the lid of the box, and found the maggot on the surface of the soil, it almost instantly proceeded to bury itself. Hope’s list records no less than nine instances of parasitism in man from the larvæ of Tenebrio molitor, and he gives a score of other Coleopterous insects which he regarded as human “intestinal worms.” Undoubtedly a large number of insect larvæ do get introduced into, and actually live within the human intestines.

Numerous cases of this sort have come under my observation, but it often requires a profound knowledge of entomology to determine the species. Several examples of œstridean larvæ occur amongst them. For one example of Œstrus hominis I am indebted to Mr Higginson, of Liverpool, who obligingly supplied me with notes of the case. Dr Kirk presented me with a small bot which he removed from Livingstone’s leg. I afterwards deposited the African bot, in his name, in the Hunterian collection. Bates speaks of an Œstrus in Brazil producing boils in human flesh. Westwood quotes similar instances. Of these, one was extracted from the thigh by Dr Brick. Mr Doubleday, the entomologist, extracted one from his own leg, and M. Goudot, another entomologist, was also victimised in the same way. Both of these savans were travelling in America at the time. Two cases from South America were also recorded by Howship. In one the larva lodged in the back; in the other in the scrotum. Humboldt noticed that the Indians were much infested by Œstridæ. Three cases are severally recorded by Roulin, Guérin, and Audouin. Mr Stroop also mentions a case in which an Œstrus was removed from an ulcer on the shoulder of a boy in Texas. Another kind of bot known as the Macaco worm (Cuterebra noxialis) occasionally attacks man, but more frequently cattle and dogs. For one example, taken from the leg of a negro, at Belize, British Honduras, I am indebted to Dr Dobson (A. M. D., Netley). Hope’s list records five cases of bots of Œstrus hominus, one of Œ. Guildingii, one of Œ. bovis, and thirteen others (belonging to the same genus) as having been noticed in man. Since his time many additional cases have been recorded by J. M. Duncan and others. In like manner a legion of cases in which the maggots of various Muscidæ have been noticed, either in, upon, or from the human body. At a meeting of the American Academy in April, 1859, Dr Leidy showed some larvæ of the bluebottle fly vomited by a child; five larvæ of the flower-fly (Anthomyia) from a physician’s own person (which had produced choleraic symptoms); and nine examples of Cuterebra noxialis. I have myself encountered numerous insect larvæ in medical practice. Amongst others I have obtained the larvæ of Anthomyia canalicularis in six or eight separate instances. One set of specimens, identified by Wunderlich, was sent to me by Dr Brandt, of Oporto. Drs Duffin, W. Fox, and Leared have supplied me with others. The larvæ described in Farre’s case, not being setose, must be referred to one or other of the Muscidæ proper. Mr Hope gave nearly forty cases of this kind, referable to eight different species of fly, and, as already implied, I have myself collected a great variety of the maggots of Muscidæ passed by the bowel, besides others obtained either from beneath the skin or from open ulcerations.

The flies hitherto noticed as supplying parasitic maggots in man are Musca domestica, M. carnaria, M. larvarum, M. nigra, and perhaps M. Cibaria, M. stabulans, and M. Cæsar. This last, a handsome fly, is the species which proves so troublesome to sheep. The habit which flies have of depositing their eggs in open wounds, when the victims are asleep, is a fertile source of this kind of parasitism. Some of the instances recorded by Kirby and Spence are revolting in the extreme. They quote the cases which came under Mr Sell’s notice in Jamaica. In one instance the flies were hatched in a neglected blister on the chest; in another from the gums and inside of the cheek; and in a third, from the nostrils of a negro, from whom 235 larvæ were expelled. The case of the Lincolnshire pauper, Page, who was literally eaten up by maggots, is almost incredible. An equally horrible instance, however, is recorded by Cloquet. It is said that the Jamaica cases were all due to the larvæ of the bluebottle fly (M. vomitoria). An instance of the same kind has been recorded by Mr Knox (A. M. D.). Sufficiently revolting as these cases are, the horrors attending them are eclipsed by the habits of the larvæ of Lucilia hominivora. The best accounts of its habits are those by M. Coquerel, M. Saint-Pair, and M. Vercammer. The insects lay their eggs in the mouth and nostrils, and when the larvæ escape they devour the tissues surrounding the buccal cavity, the pharynx, glottis, frontal and nasal sinuses, even reaching the sockets of the eye. Several Cayenne convicts have perished from the maggots of this fly, which is also prevalent in Mexico. These are not, however, the only instances of maggots gaining access to the nasal chambers. In a case recorded by Dr Astros, of Aix, 113 were discharged from the nose of a woman; and M. Legrand du Saulle records an instance where a number of larvæ occupied the frontal sinuses of a girl, nine years of age. The larvæ produced persistent headache and convulsions. In the case recorded by Wohlfart, 18 larvæ were discharged from the nose of an old man, and in the example given by Latham several larvæ were obtained from the frontal sinuses of a woman. Bracey Clark also gives an instance in which a bot was taken from a woman’s jaw. Not improbably the well-known Indian disease, termed peenash, or worm in the nose, is due to the presence of Œstridean larvæ. Cases by Rustomjee and Lahory are quoted below. Possibly Stockett’s is another of the same order. The case by Kilgour (Bibliog. No. 34) may be another. I may add that Moquin-Tandon gives an instance of the discharge of seventy-two bots, resembling those of the sheep, from a woman’s nose (‘Journ. de Vandermonde’). The rat-tail maggots or larvæ of Helophilus are parasitic. Two or three instances have been recorded from the horse. I possess one from the human intestine. Kirby also quotes an instance in which Heloph. pendulus was obtained from the stomach of a woman (‘Philos. Mag.,’ vol. ix, p. 366).

A vast number of non-parasitic insects are injurious to man and beast. Inasmuch as they subsist at the expense of their victims and also adhere to his person during their attacks for a shorter or longer time, they, like the leeches, may be spoken of as free parasites. The leg-sticker (Stomoxys calcitrans) penetrates through thick stockings, causing blood to flow freely. The clegg of the West Highlands (Hæmatopota pluvialis) also violently attacks man and beast, especially horses. The mosquito (Culex anxifer), the gnats (C. pipiens, C. annulatus, and C. pulicaris), and the midge (Chironomus plumosus) need only be mentioned. The creeping gnat (Simulium reptans) is also very annoying in Sweden. The rôle of the mosquito, as itself constituting a parasite-bearer, will be again referred to in the closing pages of this work (Book II, Section V). The bites of the tsetse (Glossina morsitans), though so destructive to the horse, ox, sheep, and dog, are not dangerous to man himself. According to Sir S. Baker, the seroot-fly, or zimb of Bruce, which is a species of Pangonia, is excessively annoying to travellers in Abyssinia. Amongst the hemipterous insects the common bug (Acanthia lectularia) is sufficiently blood-thirsty; but there is a far more sanguinary species of this kind in South America. This is the pampas benchucha (Conorhinus nigrovarius). Our distinguished countryman, Darwin, in his ‘Voyage,’ speaking of these wingless insects, says:—“Before sucking they are quite thin, but afterwards become round and bloated with blood. In less than ten minutes the insect is changed from being as flat as a wafer to a globular form.” This insect somewhat resembles our water-scorpion (Nepa cinerea), a non-parasitic species whose bite causes severe pain, as does also the wound inflicted by the water-boatman (Notonecta glauca). There are other species of bug, such as the Acanthia rotundata of Réunion Island and A. ciliata of Kasan, the bites of which are worse than that of the common species. The fly-bugs also, such as the Reduvius personatus, so common in France, and the R. amænus of Borneo and Java, attack man, although their especial habit is to attack and destroy other insects, including bugs themselves. Other species or varieties of Reduvius (R. cruentus, and R. serratus) attack man. The last named is an Indian form, capable, it is said, of producing an electric shock.

Passing to the fleas, the most important and truly parasitic form is the chigoe or gigger (Pulex penetrans). This abounds in tropical America and the West Indies. The female insects only attack man, and this they do for the purpose of securing a lodgment for their offspring. They attack especially the soles of the feet, between the toes and near the nails. In bad cases the whole of the foot becomes affected. After the insect has penetrated the skin its body swells enormously and becomes a mere bag of eggs. This swelling causes active inflammation, which terminates in suppuration and the formation of open ulcers. The chigoe also attacks various animals. In addition to the common flea (P. irritans) other species infesting animals are said to attack man occasionally. As regards those degraded types of insects known as lice I can only afford space to remark that five species have been recognised as human. These are the head-louse (Pediculus capitis); the louse of the eyelids (P. palpebrarum); the clothes-louse (P. vestimenti); the distemper louse (P. tabescentium); and the pubic louse (P. inguinalis). The distress these creatures occasion is only fully known to physicians who deal with the obstinate cutaneous affections caused by their presence (Phthiriasis). Some of the lice found on negroes and Greenlanders are regarded as distinct varieties. Lice are abundant on animals, and some of the species are apt to transfer themselves from one host to another. Thus the Ornithomyia avicularis of cage birds has been found on man, whilst one or more of the numerous species infesting the common fowl are, by transfer, apt to produce a severe phthiriasis in the horse. The lice of the fowl belong to the genera Leipurus, Liotheum, Menopon, Philopterus, Goniodes, and Goniocotes. The unsuitableness of man’s person as a habitation for bird-lice should, however, check the fear which many persons have of handling fresh-killed poultry and game birds. Poultry lousiness in man is probably impossible from this source.

Bibliography (No. 40).—Arture, “Obs. sur le ver nommé Macaque,” in ‘Mém. Acad. des Sci.,’ Paris, 1753.—Bates, “Œstrus in Man,” ‘The Naturalist on the Amazons.’—Beneden, Van, ‘Animal Parasites and Messmates,’ 1876.—Idem (with Gervais), ‘Traité de Zool. Méd.’—Blood, M., “Case of Larvæ (Musca sarcophaga) expelled alive in the Fæces,” ‘Beale’s Arch. of Med.,’ vol. iii, p. 134, 1862.—Brinton (similar case), ‘Arch. of Med.,’ vol. iii, p. 133, 1862.—Bouyer (quoted by Figuer), ‘Tour du Monde,’ p. 318, 1866.—Clark, Bracey, in ‘Linn. Trans.,’ vol. iii, 1797 (the jaw-case at p. 323), and vol. xv, 1827.—Idem, ‘Essay on Bots,’ 1815.—Cloquet, J., “Case of Blindness from Worms (larvæ of Musca) in the Eyes,” from ‘Arch. Gén. de Méd.,’ in ‘Lancet,’ 1828.—Cobbold, “On Blaps mortisaga as a Human Parasite,” ‘Brit. Med. Journ.,’ 1877, p. 420.—Idem, “Entoz.” (‘Hope’s List.’), p. 416.—Idem, in ‘Worms’ (“Leptus,” &c.), p. 140, 1872.—Coquerel (quoted by Figuer).—Cormack, J. R., “Exhibition of a Larva (B. mortisaga) passed by a Child,” ‘Month. Journ. Med. Sci.,’ vol. i, 1841.—Crumpe, S., “History of a Case in which Worms (larvæ of a beetle) were discharged from the Stomach,” from ‘Trans. of the Roy. Irish Acad.,’ vol. vi, in ‘Med. Facts and Observ.,’ vol. viii, p. 229, 1800.—Denny, ‘Monog. Anoplurorum Brittaniæ,’ 1842.—Duncan, J. M., “On the Occurrence of Bots in the Human Subject,” ‘Edin. Vet. Rev.,’ vol. i, p. 275, 1858–59.—Idem, “The Larva of Œstrus bovis in the Human Subject,” ‘Rep. of Edin. Med.-Chir. Soc.,’ in ‘Month. Journ. of Med. Sci.,’ July, 1854.—Farre, A., “On the Larva of Anthomyia canalicularis,” ‘Micr. Journ. and Struct. Rec.,’ 1841, p. 129, and in ‘Trans. of Micr. Soc. of Lond.,’ orig. ser., p. 51, 1844.—Figuer, in ‘The Insect World’ (good figs.), Janson’s edit., 1869.—Furlonge, “Anat. of Pulex,” in the ‘Journ. of the Queckett Club,’ vol. iii.—Geer, De, ‘Mémoires pour servir à l’Histoire des Insectes,’ 1773.—Gervais (see Van Beneden).—Hill, “Account of the Larva of a supposed Œstrus hominis, or Gad-fly, which deposits its Eggs in the bodies of the human species, with particulars of a Case,” ‘Edin. New. Phil. Journ.,’ vol. xxii, p. 284, 1830.—Hilaire (see St Hilaire).—Hope, “Tables of Cases of (spurious) Intestinal Worms,” ‘Lond. Med. Gaz.,’ 1837–38.—Hoppe, “Case of Larvæ of Insects (Musca stabulans) passed by Stool,” from ‘Bibl. für Läger,’ in ‘Med.-Chir. Rev.,’ 1842.—Hopper, R. S., “Insects (Stratiomis) voided with Urine,” edit. note in ‘Micr. Journ. and Struct. Rev.,’ p. 160, 1841.—Joly, ‘Recherches sur les Œstrides en général,’ &c., Lyons, 1846.—Keferstein, ‘Sur l’Oistros,’ Isis, 1827.—Kirby (and Spence), ‘Introd. to Entomology,’ 7th edit., 1856.—Knox, M., “Maggots, the larvæ of the Bluebottle Fly, in Syphilitic Ulceration of the Throat,” ‘Lancet,’ Oct. 6, 1877, p. 514.—Lahory, B. T. C., “On Peenash, or Worms in the Nose,” ‘Ind. Ann. of Med. Sci.,’ 1855, and ‘Edin. Med. Journ.,’ 1857.—Leach, “Œstridæ,” in ‘Wernerian Trans.,’ 1817.—Leidy, in ‘Proc. Phil. Acad. Nat. Sci.,’ 1859, p. 7.—Maclean, “On the Oistros,” ‘Linn. Trans.,’ vol. xiv, 1824, and in ‘Zool. Journ.,’ vol. i and iv.—Metaxa, “Vom Œstrus (u. s. w.),” in ‘Neuen Nord. Beitr.,’ Bd. i, and in ‘Mém. de Zool. Med.,’ Rome, 1835 (quoted by Westwood).—Moquin-Tandon, ‘Med. Zool.’ (l. c., Bibl. No. 38).—Newport, art. “Insecta,” ‘Todd’s Cyclop.,’ 1839.—Rustomjee, B., “Case of Worms in the Nose, or ‘Peenash,’” in ‘App. to Bomb. Med. and Phys. Soc. Trans.,’ No. vii, new ser., p. 21, 1861; see also Lahory, on ‘Peenash.’—Saint-Hilaire, “Sur l’Œstre chez l’homme,” in ‘Ann. Soc. Ent. de France,’ 1833.—Say, “Brick’s Case,” in ‘Trans. Acad. Nat. Sci. Phil.,’ vol. ii.—Sells, in ‘Trans. Entom. Soc. Lond.;’ see also Lemprière’s ‘Diseases of the Army in Jamaica,’ vol. ii.—Stockett, T. H., “An account of a Headache cured by the discharge of a Worm (?) from the Nose,” ‘Med. Com.,’ vol. xix, p. 157, 1794, and in ‘Trans. Coll. of Phys. Phil.,’ vol. i, part i, p. 181, 1793.—Stroop, St J., “Œstrus,” in ‘Amer. Naturalist,’ vol. vii, p. 437.—Tanner, “On Lice,” in his ‘Pract. of Med.,’ vol. ii, p. 429, 6th edit., 1869.—Westwood, in his ‘Classification of Insects,’ vol. ii, 1840.—Wohlfart (quoted by Moquin-Tandon).—Yule, “Case of Larvæ of Insects in the Human Stomach,” ‘Edin. Phil. Journ.,’ and ‘Lond. Med. Repos.,’ 1825.

SECTION IV.—Part VI.—Protozoa (Psorospermiæ, Gregarinidæ, &c.).

The scope of this work does not demand that I should comprise within its limits any vegetable parasites; nevertheless, I must needs refer, however briefly, to certain confervoid and sarcodic organisms, which, for the most part, lie on the borderland of the animal and vegetable kingdoms. Professor Cohn regards the bacteria as allied to the Oscillitoriaceæ. He puts them in his order Schizosporeæ. It is of little moment, practically, where these protista forms are placed. Unquestionably many of them are parasitic, as they live in the tissues, fluids, and secretions of animal bodies, including man. Their presence in cattle is associated with an anthracoid disease (charbon), whilst in the human body they have been detected in connection with zymotic affections. They have been found by Cohn, Sanderson, Klebs, Chauveau, and others, either in the lymph of vaccine pustules, or in the miliary eruptions of typhus fever. Professor Beale, who was one of the first to observe these special organic particles in vaccine lymph, denies that they are true Bacteria; and, indeed, he warmly disputes the inferences that have generally been drawn from the fact of the presence of such particles in lymph, blood, and other nutrient fluids. The best known and defined forms are Bacterium termo and Bact. lineola, which are concerned in the production of putrefaction, Bacillus anthracis, found in the blood of animals suffering from carbuncular disease, Micrococcus septicus, found in typhus and pyæmia, M. vaccinæ of cow pox lymph, and M. diphthericus, in diphtheria. As regards their prevalence in certain forms of relapsing fever, Sanderson states that Dr H. V. Carter, of Bombay, examined the blood of 250 fever patients and found spirilla in nearly every instance. From the independent observations of Pasteur, Sanderson, Lister, Tyndall, Bastian, Eberth, Roberts, Davaine, and many others, it seems clear that the Bacteria and their allies play an important part in association with certain morbid states. However, as regards the etiology of the maladies in which these organisms are found, it is perhaps too early to speak with absolute confidence. The subject cannot be dealt with here; moreover, it is outside the range of my personal investigations.

Passing to those protozoa which, although retaining some vegetable affinities, are more or less distinctively animal, I notice the obscure organisms termed psorosperms. In dealing with these I shall treat of the forms that infest both man and animals, confining my remarks to such as happen to have come under my own observation.

In the year 1865 the public were thoroughly roused to a sense of danger arising from the consumption of meat. The panic originated with the outbreaks of trichiniasis in Germany. During the excitement which subsequently prevailed at the time of the rinderpest, all sorts of erroneous notions took possession of the popular mind, and the errors were stimulated by writers ignorant of helminthology. In January, 1866, I published a few observations, the purport of which was to show that certain microscopic organisms found in animals dying from cattle plague were harmless “parasitic Protozoa,” possessing more or less striking vegetable affinities. About a week previously some interesting researches on these so-called cattle-plague bodies had been published by Dr Beale. Those who first saw these bodies thought they had stumbled upon organisms new to science. I showed that similar or analogous organisms were to be met with in a great variety of animals, and likewise in the human body. They had been called worm-nodules, worm-nests, egg-sacs, eggs of the common fluke, young “measles,” corpuscles produced by muscular degeneration, psorospermiæ, stages of growth of gregarinæ, amœboid bodies, and so forth. In so far as the higher animals were concerned, Dujardin was the first to describe them. He found these organisms in a mole. This animal, however, having been fed upon earth-worms known to harbour such parasites, there was no difficulty in accounting for the source of the psorosperms.

In 1853 Hessling discovered psorospermial sacs in the muscular substance of the heart, not only of the ox, but also of the sheep and roe. By him they were regarded as evidences of muscular degeneration. About ten years previously Miescher found similar bodies in the muscles of the mouse.

In 1857 Rainey described similar structures taken from the flesh of swine; and, in his memoir, he went so far as to maintain that these bodies were early stages of development of the common pork-measle. In the year 1858 Gubler wrote an important paper on this subject, in which he related a case where twenty cysts existed in the human liver. The cysts were of great size, mostly as large as a hen’s egg, one of them being some six inches in diameter. Naturally, the largest had been diagnosed as an ordinary hydatid. However, on evacuating their contents (post mortem), they were found to harbor enormous quantities of minute corpuscles strictly analogous to those usually obtained from psorospermial sacs. Gubler believed he had stumbled upon masses of eggs of Distoma hepaticum, but in this he erred. Shortly after Gubler’s discovery similar bodies from the human liver were described by Virchow; and in 1862, the subject was followed up by Dr Dressler, of Prague. Dressler found in the human liver a number of pea-shaped bodies, the milky contents (breisubstanz) of which displayed a multitude of the characteristic corpuscular elements referred to. These particles, already considered as equivalent to, if not identical with, the so-called pseudo-navicellæ of gregarinæ, were soon encountered by a variety of independent observers. Thus, Leuckart noticed these bodies in various animals; but with caution remarked:—“Concerning the nature of these formations I will not decide. To be candid, however, it appears to me to be in no way made out whether the psorospermiæ are to be considered as the result of a special animal development, whether they, like pseudo-navicellæ, are the nuclei of gregariniform productions, or whether they are the final products of pathological metamorphosis.” Leuckart found these organisms in the intestines of a trichinised dog, also in a sheep and pig fed with Trichinæ. He also found them in the muscles of another pig fed with psorosperms, and likewise in the liver of various rabbits. He remarks that in swine these parasites are more abundant than measles. They were present in five of eighteen pigs, and also in two out of four sheep, whose flesh was especially examined. The observations of Lindemann at Nischney-Novgorod are particularly interesting. This medical officer discovered psorospermial sacs attached to the hair of a girl who was being treated in hospital for chlorosis. The sacs in question bore close resemblance to the bodies which we found in abundance in diseased and healthy cattle. It would further appear, from Lindemann’s observations, that the affection is not very uncommon amongst the Russian peasants.

In connection with and attached to the same parasitically affected hairs Lindemann also noticed several movable gregarinæ; and partly from this circumstance he was led to believe in the existence of a genetic relation subsisting between the two kinds of bodies. He further expressed his conviction that the people contracted the disease by washing themselves with water in which gregarinæ abounded. Lindemann moreover refers to Lebert as having noticed similar parasites in a case of favus, and concludes that these organisms are of a vegetable nature. His opinion, though not shared by the majority of parasitologists, is nevertheless supported by the views of Robin, Leydig, and others. Of still higher interest are the observations of Lindemann respecting the occurrence of psorospermiæ in the capsule of the kidney of a hospital patient who died with Bright’s disease. The sacs in this case were remarkably small; nevertheless their corpuscular contents indicated their true nature. The pseudo-navicellæ measured only 1/5000″ in diameter. Amongst other contributions of interest I may refer to those of Dufour, J. Müller, Creplin, Kölliker, Keferstein, Stein, Drummond, Lieberkühn, and E. Ray Lankester. I doubt if the vegetable organisms described by Prof. W. T. Gairdner can be referred to this group of parasites. At all events, by whatever name these spurious entozoa are called, they were first discovered by Dufour in insects, by Müller in fishes, by Miescher in the mouse, by Dujardin in the mole, by Hessling in the larger quadrupeds, and by Gubler in man. The results of my own examinations may be briefly re-stated. In the flesh of cattle I found psorospermial sacs varying from 1/120″ to 1/12″ in length, and in that of sheep from 1/220″ to 1/80″. The bodies were enclosed in well-defined transparent envelopes, and their contents exhibited indications of segmentation. In some specimens the segments displayed themselves as a complete cell-formation, the contents of each cell being uniformly granular. Under the 1/4″ objective the contained granules were clearly visible, and on rupturing the sac their peculiar characters were at once manifest, each granule or corpuscle represented a pseudo-navicel, all displaying a tolerably uniform size, averaging 1/2000″ in diameter. Some of the corpuscles were round, others oval, several bluntly pointed at one end, many curved and fusiform, not a few being almost reniform. Highly refracting points or nucleoli were visible in their anterior.

Turning to the practical aspect of the subject, I remarked that these bodies had nothing to do with the cattle plague. No one who carefully examined the flesh of animals that had died of rinderpest had failed to discover them; yet, in one or two instances they appear to have escaped notice. When it is considered how long it takes us to examine a few grains weight of muscle carefully, it is obvious that the body of a large beast might contain many hundreds of these organisms without our being able to detect their presence, except by a prolonged investigation. In the few rinderpest beasts, portions of whose flesh I submitted to the microscope, I should say there were not more than 100 of these bodies in one ounce of meat; but in the heart of a healthy sheep (which I afterwards ate) I calculated there were about 1000 parasites to the ounce, and in the heart of a healthy bullock (which likewise served me for a meal) their numbers were rather in excess of those in the sheep. Altogether, at two meals, I could not have swallowed less than 18,000 of these psorosperms. Consumers of beef, mutton, and pork eat these bodies every day, but they take no harm because the parasites in question are not true helminths. Fine healthy beef has been returned to the butcher when it was as good as any other meat in the market. I have examined various kinds of meat, such as veal, pork, and mutton, but in none have I found so great an abundance of psorosperms as in beef, which was, notwithstanding, perfectly healthy and sound. I calculated that in one instance a single ounce of the flesh contained upwards of 2000 parasites. There is practically no limit to the extent of this kind of parasitism, and there is no organ of the body in which psorosperms may not be found. Moreover, the forms they display are exceedingly various. Psorosperms have been found by Siedamagrotzky in the muscles of the horse, and not very long ago, through the help of Professors Simonds and Axe, I had the opportunity to examine some peculiar worm-like structures which occupied the mitral valve of a horse. To the naked eye they looked like coiled nematodes, but I was soon convinced that they formed a peculiar type of psorosperm. A complete view of these bodies was a matter of great difficulty owing to the delicate nature of their limiting membrane and to the confusion of markings produced by the interlacing of the fibres of the chordæ tendinea. At length, by spreading a portion of the membrane of the valve over a large glass slide, and by allowing it to dry slowly, I found that the vermiform body presented neither beginning nor end. The appearances were curious and puzzling. The organism formed a flattened tube or sac, almost uniform in width and variously twisted upon itself. From the main tube there projected several hernia-like secondary loops or branches, most of them presenting less than half of the thickness of the former. These peculiarities, however, can hardly be understood without reference to the original illustrations. That these secondary coils were not of the nature of hernial protrusions was evident, not alone from the nature of their contents, but also from the fact that they showed distinct anastomoses. In fact, the parasite was a simple sac or bag with branches.

On puncturing the main tube with a fine needle a small quantity of tenacious creamy fluid made its escape. This, under Ross’s 1/4-inch lens, resolved itself into a few excessively delicate sarcode globules surrounded by fine granules. The granular matter displayed a tendency to collect itself in the form of oval masses without showing any trace of a limiting border. One of these masses, measuring 1/250″ in length, I examined under a Wasserlein-objective, when I further ascertained that the elementary particles or granules were uniformly oval in shape, rather highly refractive, their size scarcely exceeding 1/8000″ in diameter. The sarcode corpuscles, on the other hand, were of different sizes, ranging between 1/3000″ and 1/1600″ in diameter.

From the facts thus elicited, negative as they were in respect of helminthic structure, I could see no escape from the conclusion that we had to deal with a new form of psorospermial bag, whose granular contents consisted of excessively minute pseudo-navicellæ. In the centre of the largest hernia-like loop there was a clear oval disk, which at first brought to my mind the nucleus of Monocystis infesting the earth-worm, but it was merely a vacuole.

The case recorded by Gubler reminds me of another remarkable instance of psorospermial cysts, in this case associated with true hydatids. In 1873 Dr Whittell sent me particulars of a case in which the contents of an hydatid of the liver (drawn off, during life) consisted of shreds of a true hydatid, a few echinococcus-hooklets, together with multitudes of spindle-shaped amœboid particles of excessive minuteness and delicacy. The bodies, floating in a transparent fluid, formed a thick milky or creamy fluid, resembling pus in appearance; but there was no trace of pyæmia. Judging from Dr Whittell’s figures, he must also have found a solitary microscopic nematoid hæmatozoon, the nature of which was not clear to him. I believe it to have been a specimen of Filaria sanguinis hominis. Be that as it may, the case is altogether unique and deserves further elucidation.

As regards the higher forms of protozoa it must suffice to allude to the Cercomonas hominis of Davaine, found in the dejections of cholera patients, to the Cerc. urinarius of Hassal and C. saltans of Ehrenberg, to the Trichomonas vaginalis of Donné, detected in the vaginal mucus, and to the Balantidium coli of Claparède and Lachmann, originally found by Malmsten in the human colon. The Balantidium, or Paramæcium coli, has frequently been observed in the evacuations of fever patients, and it has also been found by Dr Treille in patients suffering from the Cochin-China diarrhœa. Monads have also been found in the stomach and intestines of the hog and various other animals. Infusorial parasites are particularly abundant in batrachians, the Bursariæ of frogs and toads being familiar to every helminthologist.

Bibliography (No. 41).—Arloing (and Tripier), in ‘Gaz.-hebd.,’ 1873, p. 574 (quoted by Davaine).—Balbiani, ‘Compt. Rend. Soc. Biol.,’ 1867, p. 103 (quoted by Davaine and Bastian).—Bastian, “On the Nature of the so-called Sarcina ventriculi,” ‘Brit. Med. Journ.,’ Feb. 3, 1872.—Idem, “On Heterogenesis in its relation to certain Parasitic Diseases,” ‘Brit. Med. Journ.,’ Feb. 24 and April 20, 1872 (see part iv, p. 417, with figs. from Balbiani).—Beale, L., “Entozoon-like bodies in Muscles,” in the ‘Microscope in Medicine,’ 4th edit., p. 485, 1878.—Idem, “Bacterium Hypothesis of Contagium,” ibid., pp. 313–321.—Burnett, W. T., “On Psorospermia, Mermithes, &c.,” in a paper entitled ‘Reviews and Records in Anat. and Physiol.,’ in ‘Amer. Journ. of Sci. and Arts,’ vol. xviii, 2nd ser., p. 104, 1854.—Carter, H. V., “On Spirilla,” quoted by Sanderson in ‘Brit. Med. Journ.,’ Nov. 17, 1877, p. 700.—Cobbold, “Remarks on Spurious Entozoa found in Diseased and Healthy Cattle,” ‘Path. Soc. Trans.,’ vol. xvii, p. 452, 1866, and ‘Lancet,’ Jan. 27, 1866, p. 88; see also Prof. J. Gamgee’s work on the ‘Cattle Plague.’—Idem, “On Worm-like Organisms in the Mitral Valve of a Horse,” ‘Veterinarian,’ Sept., 1877.—Idem, “On Psorospermiæ in the Eye of the Cod (Morrhua),” ‘Linnean Society’s Proc.,’ May, 1862, and in ‘Intellectual Observer,’ 1862, p. 199.—Cohn, ‘Nova Acta,’ xxiv, s. 103 (quoted by Leuckart), Bd. i, s. 139.—Creplin, ‘Wiegmann’s Archiv,’ 1842, s. 61.—Davaine, l. c., 2nd edit., “Synops. xxi” (with bibliog. refs.), 1878.—Donné, ‘Cours de Microscopie,’ Paris, 1847, p. 157.—Dressler, quoted by Leuckart, Bd. i, s. 141.—Drummond, ‘Edin. Phys. Rep.,’ 1852,—Dufour, ‘Ann. des Sci. Nat.,’ 1837.—Dujardin, ‘Traité’ (l. c., see Bibl. No. [1]).—Eberth, ‘Zur Kentniss Bacteritischer Mykosen,’ 1872.—Eimer, ‘Ueber Psorospermien,’ 1870.—Gairdner, ‘Edin. Phys. Soc. Rep.,’ 1853.—Gluge, “Cysts in Sticklebacks,” ‘Bullet. Acad. Roy. des Sci. de Bruxelles,’ 1838.—Gubler, ‘Mem. Soc. Biol.,’ 1859, p. 657, and in ‘Gaz. Méd.,’ 1858, p. 61.—Harz, C. O., “Eine neue Mikrococcusform im lebenden Thierkörper,” ‘Deutsche Zeitschrift für Thier-Medicin und vergleichende Pathologie,’ f. Novemb., 1878.—Hessling, ‘Sieb. u. Köll. Zeitsch.,’ 1853, p. 196.—Henle, ‘Müller’s Archiv,’ 1845.—Hollis, W. A., “What is a Bacterium?” repr. in the ‘Veterinarian,’ p. 205, 1875.—Keferstein, ‘Götling. gelehrte Anzeigen,’ 1862.—Kloss, ‘Ueber Parasiten (u. s. w.)’ (quoted by Davaine).—Knoch, ‘Journ. de Russ. Kriegs. dep.,’ Bd. xcv, 1866 (quoted by Leuckart and by Davaine).—Kölliker, in ‘Zeitsch.’ (by Sieb. and Köll.), 1848–49.—Lambl, ‘Prager Vierteljahrschrift,’ 1859.—Lankester, E. R., “Recent Researches on Bacteria (with copious references),” ‘Quart. Journ. Micr. Science,’ Oct., 1878.—Lebert, ‘Phys. Pathologique’ (quoted by Leuckart).—Leidy, “Gregarina,” ‘Amer. Phil. Trans.,’ 1851.—Leisering, “Bericht (u. s. w.),” in ‘Sachsen,’ 1865.—Leuckart, l. c., Bd. i, s. 135 and 740, and Bd. ii, s. 842 et seq.—Leydig, ‘Müller’s Archiv,’ 1851, s. 221, in ‘Micr. Journ.,’ 1853, p. 206, and in ‘Arch. f. Anat. und Phys.,’ 1863, s. 191.—Lieberkühn, ‘Müller’s Arch.,’ 1854.—Lindemann, ‘Bullet. Soc. imp. des Naturalistes de Moscow,’ 1863, and in ‘Gaz. Méd. de Paris,’ 1870, p. 86.—Lister, J., “Natural History of Bacteria,” ‘Micr. Journ.,’ Oct, 1873.—Malmsten, “Paramæcium coli” (quoted by Davaine, l. c., 2nd edit., p. 67).—Miescher (quoted by Leuckart and Siebold).—Müller, ‘Archiv,’ 1841, s. 477.—Rainey, ‘Phil. Trans.,’ 1857.—Rayer, “Singulière éruption sur un véron (Cyprinus),” ‘Arch. de Méd. Comparée,’ Paris, 1842 (quoted by Davaine).—Rivolta, “Psorospermi, &c.,” trans. in ‘Journ. des Vét. du Midi,’ 1869, pp. 445 and 521.—Robin, ‘Les Végét. Paras.,’ 2nd edit., p. 291.—Sanderson, in ‘Privy Council Reports,’ 1874.—Siedamagrotzky, in ‘Recueil de Méd. Vét.,’ 1872, p. 460.—Stein, in ‘Müller’s Arch.,’ 1848, and ‘Ann. Nat. Hist.,’ 1850.—Idem, “Abhandl. d. k. Böhmischen Gesellsch.,” x, s. 69, oder Lotos, 1859, s. 57 (quoted by Leuckart, Bd. i, s. 151).—Steinberg, ‘Walter’s Zeitschr. f. die moderne Medicin,’ 1862, and in Leuckart, Bd. ii, s. 844.—Stieda, ‘Arch. f. pathol. anat.,’ Bd. xxxv, and in Leuckart, Bd. ii, s. 846.—Suriray, “Sur quelques parasites du lombric,” ‘Ann. des. Sci. Nat.,’ 1836.—Virchow, “Zur Keutniss der Wurmknoten,” ‘Arch. f. Anat. u. Phys.,’ xviii, s. 523.—Vogel, ‘Path. Anat.,’ i, s. 404.—Waldenburg, “Psorospermien,” in ‘Arch. f. Path. Anat.,’ s. 435, 1867.—Windbladh, also Wising, ‘On Balantidium coli’ (quoted by Leuckart, Bd. ii, s. 846–847).—Winkler (see Leisering).

Appendix.—On various occasions I have dwelt upon the necessity of acquiring accurate information respecting the degree of mortality due to parasites, and in the present volume (p. [124]) I have referred to the defective evidences supplied by the returns of the Registrar-General in respect of the echinococcus disease. My object is not to cast blame upon those whose duty it is to publish the returns, but rather to call attention to the advantages that would follow if the Registrar-General were supplied with full and accurate information on this head.

Through the courtesy of Mr Noel A. Humphreys I have been furnished with the following official statement of the number of Deaths from Worms in England and Wales, as recorded in the Annual Reports of the Registrar-General throughout a decade of years:

1868186918701871187218731874187518761877
Total172148151160154183188227204225
Including— 
Porrigo15131919191415161713
Scabies161217111412—151213
Tapeworm18131613151315151216
Hydatids20203337413429433151

Considering the prodigious advances in helminthology during the last half century, it is certainly remarkable that under the category of “worms,” as a cause of death, only two kinds of true helminths should be mentioned in the Registrar’s record. It will also strike the experienced hospital and dispensary physician as somewhat remarkable that of the two death-producing parasites above named one of them should be the “tapeworm.” Now death from Tænia is certainly a very rare occurrence, although grave nervous symptoms are not unfrequently due to its presence in man. Thus, I am inclined to regard the 46 reported instances of death from this cause as a redundant estimate. On the other hand, I am surprised to see no specified instances of death from lumbricoid Ascarides, from Oxyurides, or even from Cysticerci, which now and then take up their residence in the human brain.

As regards hydatids I believe the returns to be excessively deficient. In place of an average of 34 deaths annually from this cause in the United Kingdom I am of opinion that at least 400 deaths are due to hydatids. This opinion and the data on which it was founded were communicated by me twelve years ago to the Linnean Society, and I have since become acquainted with facts which lead me to conclude that my original estimate was very much below the mark. The post-mortem registrar of one of our large hospitals has told me that of late years as many as ten deaths might be reckoned as annually due to hydatids in their institution alone. At a smaller hospital I ascertained that the average was about four. Obviously, if these estimates are correct, the Registrar-General’s returns for the United Kingdom do not record a tithe of the annual mortality due to hydatids. Perhaps another half century will elapse before the truth of my deductions be confirmed by the official returns. For me, it must suffice to have pointed to the desirability of securing more accurate records.

By a curious coincidence I had only just sent to press the sheet of this work recording the statistics of hydatid disease in Australia (p. [123]), when a paper dealing with the same subject appeared in the ‘Lancet.’ I refer to the brief memoir of Dr David Thomas, of Adelaide, South Australia, which was published on the 1st of March, 1879. Dr Thomas writes as follows:

“It is well known that Australia presents an extraordinary prevalence of hydatid disease, but, as far as I know, no definite statistics have been published to illustrate the fact. Consequently, some months ago, with the kind assistance of the Hon. W. Morgan, the present Chief Secretary of South Australia, I endeavoured to procure reports from the Governments of Victoria, New South Wales, Queensland, New Zealand, Tasmania, and Western Australia, upon this question. Unfortunately, the mode of registration of the causes of death in most of these colonies was such as prevented the necessary replies being supplied. However, it appears that in Tasmania no deaths were returned from this disease in the ten years 1867–77. During the greater part of the same period no separate classification of hydatid disease had been adopted in New South Wales; but in 1875 four deaths were attributed to hydatids; in 1876, eleven were so returned. In Victoria, however, the record of deaths from this cause is far more complete, and I append a table based upon the returns from that colony.

“One case, in which hydatid of the kidney was present, accompanied by malignant disease of bladder, with stricture, was not returned as a case of hydatid causing death.

“During the decade 1867–77, 2·5 per 1000 deaths were due to hydatid disease. In 183 out of the 307 cases the liver was either solely or conjointly with other organs the seat of disease. Holding the second place in frequency come the lungs in 71 cases, i.e. 53 simple and 18 complicated.”

Table of Deaths returned as being due to Hydatid Disease in the Province of Victoria during the ten years 1867–77.

Year.Liver.Lungs.
and
pleura.		Brain and
spinal
cord.		Heart and
peri-
cardium.		Kidney.Spleen.Pan-
creas.		Omen-
tum.		Ovary.Womb
(?)		Abdom-
inal
cavity.		Situation
not
recorded.		More
than one
organ
invaded.		Total
annual
deaths.
186811715112171(a)33
1869116181112113(b)22
18701101211417
187111416111111(c)15
1872119131112121(d)29
1873117132125(e)29
18741211011162(f)41
18751291721113122(g)47
187612311211145(h)36
18771201811113122(i)38
Totals1665375232111?133122307 in 10 yrs.
(a)Lungs and kidneys.
(b)In two instances liver and lungs; in the third case liver and brain.
(c)Lungs and liver.
(d)Lungs and abdominal cavity.
(e)In three cases liver and lungs; in one kidney and abdomen; in another liver, lungs, omentum.
(f)Liver and lungs.
(g)One liver and lungs; the second case lungs and heart.
(h)Three cases liver and lungs; one liver and kidney.
(i)Liver and lungs.

Such are the returns as recorded by Dr Thomas. If a comparison be instituted between the data supplied by his decade-report and those supplied by the decade-report which I have previously adduced (p. [123]), it will be seen that as regards the returns for the years 1868–72, inclusive, both reports are in perfect agreement. Of still more interest also is the circumstance that whilst, on the one hand, out of the total of 307 deaths given in Dr Thomas’s table, 116 occurred during the first semi-decade (i.e. from 1868 to 1872, inclusive), on the other hand, no less than 181 deaths occurred during the second semi-decade (i.e. from 1873 to 1877, inclusive). This increase of 45 deaths during the later semi-decade is very significant. It points either to the fact of more careful returns having been made, or to an actual increase in the fatality of the disorder. Possibly both the causes alluded to operated to affect the returns. Be that as it may, Dr Thomas’s record is highly instructive, and should stimulate the profession in England to supply our Registrar-General with more precise data wherewith to construct his annual reports.