In the autumn of 1872 I caused a lamb to be fed with the proglottides of a tapeworm which I referred to this species. The animal was slaughtered on the 22nd of January, 1873, when the result was stated to have been negative. As I had no opportunity of examining the carcase, I cannot feel quite sure that there actually were no Cysticerci present. On several occasions I have detected measles in the flesh of animals, when none were supposed to be present by those who either assisted me or were professional on-lookers. Assuming my Tænia tenella to be derived from the sheep’s Cysticercus, I think it fitting to describe the mutton measle in this place. Even if T. tenella be not actually the adult representative of the mutton measle (Cyst. ovis), it is quite certain that the scolex in question gives rise to an armed tapeworm, and it is almost equally certain that the adult armed cestode resides in man. In Pruner’s case, which is by no means unique, we have seen that two distinct species of cestode may coexist in the human bearer. It is quite possible that some one may yet have the good fortune to detect the beef tapeworm, the pork tapeworm, and the mutton tapeworm, all together in one and the same host.
On five separate occasions I have detected measles in “joints” of otherwise excellent and healthy mutton brought to my own table, and supplied by the family butcher. On several other occasions I have had these parasites brought under my notice; nevertheless, many persons are either unaware of, or actually deny, the existence of these ovine parasites. Thus, MM. Masse and Pourquier, in the ‘Montpellier Med. Journ.’ for Sept., 1876, make the following statement: “The sheep, not being subject to measles, it seems to us natural to employ the raw meat of that animal whenever it is required for nourishment in the treatment of diarrhœa, in weaning children, in phthisis, and for anæmics.” Clearly, if MM. Masse and Pourquier could have brought themselves to believe that English literature is worth consulting on such matters, they would not have made this statement. Incidentally they also observe, when speaking of beef measles:—“Un fait que nous avons remarqué et que nous tenons à signaler, c’est que nous avons trouvé des cysticerques nageant librement dans l’eau où nous avions plongé de la viande infestée de ladrerie.” Certainly this is a novel experience. That measles should not only get out of their cysts, but should have the power of “swimming freely” in the water is a phenomenon which requires explanation. There must have been some error of observation.
It was in the year 1865 that I discovered the mutton measle (C. ovis, mihi); but I am not prepared to say that the parasite had never been seen before, since it is alleged that a two-headed Cysticercus was obtained by Fromage from the liver of a sheep (as cited by Davaine). Be that as it may, my discovery was announced in a communication made at the Birmingham meeting of the British Association in the autumn of 1865, and subsequently at a meeting of the Pathological Society of London, on the 3rd of April, 1866 (‘Path. Trans.,’ vol. xviii, p. 463). After these dates further announcements and verifications appeared, amongst which I can only refer to my remarks “On Beef, Pork, and Mutton, in relation to Tapeworms,” forming an appendix to the first edition of my work on Tapeworms, 1866; to the “Remarks on Cysticerci from Mutton,” contained in the fourth chapter of the Supplement to my introductory treatise on Entozoa, where a figure of the parasite is given, 1869, p. 27; to Dr Maddox’s paper “On an Entozoon with Ova, found encysted in the Muscles of a Sheep,” recorded in ‘Nature,’ May 15th, 1873, p. 59; to the ‘Monthly Microscopical Journal,’ June, 1873, p. 245; to my further communications in the ‘Lond. Med. Record,’ Aug. 6th, 1873; to my ‘Manual,’ 1874, pp. 74 and 105, Ital. edit. ‘Nota Dell’ Autore,’ p. 133; and especially to the article headed “The Mutton Tapeworm,” contained in the 3rd edit. of my little volume on ‘Tapeworms,’ p. 12, et seq., 1875.
In regard to the measle itself, I spoke of it as smaller than the common pork measle. The head is 1/30″ in breadth, and is armed with a double crown of hooks, twenty-six in all, the larger hooks each measuring 1/160″ in length. The suckers are four in number, each having a breadth of 1/100″. The neck and head are abundantly supplied with calcareous corpuscles, being at the same time marked by transverse rugæ. The data on which I founded my brief description of the scolex were chiefly based on the examination of a specimen which had been procured by Prof. Heisch from the interior of a mutton chop. Subsequently much fuller details of the structure of the scolex were supplied by the illustrated memoir of Dr Maddox (above quoted). This excellent microscopist, however, announced the presence of immature ova within the Cysticerci themselves. As the notion of the existence of eggs in larval cestodes was altogether at variance with what we know of the phenomena of tapeworm life, I suggested that the author might have mistaken the egg-shaped calcareous corpuscles (which I found so abundant in my own specimens) for the ova. In the interests of truth I felt bound to characterise certain of the conclusions arrived at by Dr Maddox as simply incredible, but I regarded his memoir as forming “an important contribution to our knowledge of the structure of the mutton measle.” I had no idea that in pointing to errors of interpretation I should offend the excellent author. However, a long letter appeared in the ‘London Medical Record,’ in which Dr Maddox showed that he was much vexed that I should have “impugned” the “accuracy of his conclusions.” He defended his position with the support of no less an authority than Dr Macdonald, F.R.S., the distinguished Assistant Professor of Naval Hygiène at the Victoria Hospital, Netley. Dr Maddox says:— “We were quite alive to the anomalous position. Hence the exceptionability of the case rests on more than my own evidence.” In regard to this unfortunate dispute I will only add the expression of my conviction that Drs Maddox and Macdonald will eventually become satisfied that no cestode scolex is capable of displaying either mature or immature ova in its interior.
Bibliography (No. 15). Cobbold (l. c., supra), 1865–75.—Idem, “On Measly Meat, &c.,” the ‘Veterinarian,’ Dec., 1876.—Idem, “The Mutton Tapeworm (T. tenella),” No. 16 in my revised list of Entozoa, the ‘Veterinarian,’ Dec., 1874.—Diesing, C. M. (Tænia tenella, Pruner nec Pallas), in “Revis der Cephalocotyleen,” ‘Sitzungsb. der Math.-Mat. Class d. k. Akad. der Wissenschaften,’ Bd. xlix, s. 369, 1864.—Maddox (l. c., supra), 1873.—Mayrhofer, J. C., ‘Die helminth. des Menschen,’ Erlangen, 1854.—Pruner, ‘Krankheiten des Orients,’ s. 245, 1847.
Tænia lophosoma, Cobbold.—This is a good species notwithstanding the doubts that have been expressed by Heller and others regarding it. I have called it the ridged tapeworm in consequence of the presence of an elevated line coursing the whole length of the body, which measures about eight feet. The reproductive papillæ are remarkably prominent and uniserially disposed throughout the entire chain of proglottides. It is quite an error to suppose that this species is a malformed cestode, or that it has any resemblance to Küchenmeister’s variety of tapeworm from the Cape of Good Hope. Neither does it in the slightest degree resemble the remarkably malformed T. mediocanellata described by Mr Cullingworth. Of the distinctiveness of this parasite as a species, any one may satisfy himself by an inspection of the nearly complete strobile preserved in the Pathological Museum attached to the Middlesex Hospital Medical College. From the examination of several mature proglottides detached from this specimen, I find their average breadth to be one fifth of an inch, by three quarters of an inch in length. Their greatest thickness does not exceed the 1/13th of an inch. The eggs resemble those of other tapeworms, and offer a diameter of about 1/850″ from pole to pole.
Bibliography (No. 16).—Cobbold, “Parasites of Man,” in the ‘Midland Naturalist,’ April, 1878, p. 98.—Idem, ‘Tapeworms,’ 1st edit., p. 52, 1866; 3rd edit., p. 27, 1875.—Cullingworth (see Bibl. No. [18]).—Davaine, ‘Les Cestoïdes,’ l. c., p. 573.—Heller, l. c., s. 594.
Tænia nana, Siebold.—As regards the dwarf tapeworm, unless Spooner’s case be genuine, there is but one solitary instance on record of its occurrence in the human body; moreover, we have no evidence of its having existed in any other host. It was discovered by Dr Bilharz, of Cairo, at the post-mortem examination of a boy who died from inflammation of the cerebral membranes. Prodigious numbers existed. The largest specimen measured only one inch in length. To the naked eye these worms resemble short threads, and consequently they might very readily be overlooked. The head is broad and furnished with a formidable rostellum armed with a crown of hooks. These hooks have large anterior root-processes, which, extending unusually forward, impart to the individual hooks a bifid character. By far the best account of this worm is furnished by Leuckart, to whom I am indebted for a specimen.
Bibliography (No. 17).—Cobbold, ‘Entozoa,’ p. 244.—Davaine (l. c., Bibl. No. 2), p. 574.—Heller, l. c., s. 606.—Küchenmeister, l. c., Eng. edit., p. 141.—Leuckart, l. c., Bd. i, s. 393.—Von Siebold and Bilharz, in Von Sieb. and Köll. Zeitschr., Bd. iv.—Spooner, ‘Amer. Journ. Med. Sci.,’ 1873.—Van Beneden, ‘Iconographie,’ l. c., pl. iii, fig. 17.—Weinland, ‘Diplacanthus nanus,’ l. c., p. 85.