When describing the parasites of the horse (p. [358]), I spoke of Collins’ amphistome from that animal, but in the letter addressed to me from Simla, 22nd March, 1875, Mr. Collins made no allusion to the earth-eating habit. He wrote:—“I forward you by this mail parasites found in the colon of a horse that died, a subject of fever peculiar to this country. There were about a thousand of the parasites, and nearly the whole of them were situated close to the cæcum, and were loose in the gut. Not having seen parasites at all similar to these, I have forwarded them for identification. They were of a brick-red color when first obtained.” These explicit statements by Mr Collins are interesting from many points of view. One has only to place his specimens side by side with those from the elephant in order to satisfy one’s self that the two forms are distinct. For the reasons already stated I provisionally called the worm Amphistoma Collinsii. It is probable that other veterinary surgeons have encountered this entozoon in India; but, unless they can point to some published account of the fact, Mr Collins is entitled to be considered as its discoverer. Doubtless many other European residents in India, Ceylon, and Burmah, must, like Dr Gilchrist, be well acquainted with the masuri as such, though unaware of their zoological position.
In a record of the post-mortem examination of one of the victims of the Secunderabad epizoöty, the veterinary surgeon said:—“No doubt disease of the lungs and subacute inflammation of the bowels were the immediate cause of death, but the large number of flukes in the liver and the intestinal parasites (i.e. the amphistomes) account in a great measure for some of the symptoms shown, and these symptoms accord in many respects with those shown in elephants that died in Burmah during the epizoöty (rot) in 1867, as recorded by R. B., notably, refusal of food, standing with mouth open, restlessness, and puffiness about the head and shoulders. The liver parasite is no doubt the same referred to by R. B., and is that termed by Dr Cobbold Fasciola Jacksoni.” In reference to a later case the same officer remarks:—“I carried out the post-mortem examination with special reference to inquiry as to the probability of the mortality amongst elephants at this station being of parasitic origin. This was suggested to me by the former case. The post-mortem appearances differed in every respect. There were flukes in the liver, but in no great quantity, and the structure of the liver was sound. Although not assisted by this case in attributing the mortality to parasitic origin, I am strengthened in my opinion that the death of the previous elephant was due to disease caused by the presence of the liver fluke.” This report, by Mr W. S. Adams, is to some extent in harmony with later information. An epizoötic outbreak amongst elephants has occurred in England, at Sanger’s Circus, and I had opportunity to examine one of the dead animals. In my own opinion, and in that of Mr F. Smith, the veterinary surgeon who attended the animals professionally, the disease was due to parasites. I obtained large quantities of Amphistoma Hawkesii from the intestinal canal, and also other worms. The death of one of the elephants was made the subject of litigation, when, as might be expected, great diversity of opinion as to the cause of the fatal issue prevailed.
Mr Smith, an old pupil of mine, regarding the amphistomes and strongyles as the cause of death, wrote to the effect that “some of the worms were found between the coats of the intestine, and others on the free surface of the gut, whilst the excretory ducts of some of the glands were found blocked with them.” The animal examined by myself on the 24th of August, 1876, yielded numerous examples of Amphistoma Hawkesii, Ascaris lonchoptera, and Dochmius Sangeri, the last species being so named by me after the owner of the circus who lost the herd of elephants by the epizoöty. The male Dochmii measured 5/8 and the females 3/4 of an inch in length. Here I must reluctantly quit the helminths of elephants, adding only an expression of surprise that Dr Max Schmidt should have had so little to say concerning them in his otherwise instructive memoir on ‘The Diseases of Pachyderms’ (quoted below).
I have but a few words to offer respecting the ectozoa. A species of mite has been described whose generic position appears doubtful. I allude to Homopus elephantis of Fürstenberg, or Symbiotes elephantis of Gerlach. According to Mégnin it is a nymphe adventive or hypope of a variety of Tyroglyphus siro. This acarus is abundant in old forage. Another ectozoon is Hæmatomyzus elephantis. It differs from the lice proper in many respects, but, according to Piaget, the reproductive organs resemble those of Hæmatopinus. In ‘Science Gossip’ for June, 1871, Mr H. C. Richter describes “a new form of parasite,” which is called Idolocoris elephantis. The insect, which was one line in length, was found upon an elephant in Ceylon. According to Walker it not only constituted the type of a new genus, but of an altogether new family of the Hemiptera Heteroptera, coming very near to the bed-bugs (Acanthidæ). It is a huge sucking louse. From the discussion which followed, it seems that the parasite had several times been seen before, and was none other than E. Piaget’s Hæmatomyzus elephantis. Excellent figures accompany Richter’s and Piaget’s descriptions. Notwithstanding Piaget’s explanation, I think the specific name, longirostris, would have been a more appropriate appellation.
Bibliography (No. 51).—(Anonymous), “Diseased Elephants,” see ‘Lancet,’ Sept. 2, 1876; also “Report of the Case at Law (Jamrach v. Sanger),” given in the ‘Veterinarian,’ Dec., 1877, p. 886.—Cobbold, T. S., “Description of a species of Trematode from the Indian Elephant, with remarks on its Affinities,” ‘Quart. Micros. Journ.,’ Jan., 1869; see also ‘Entozoa,’ supp., 1869, p. 80.—Idem, “On the Destruction of Elephants by Parasites, with remarks on two new species of Entozoa and on the so-called Earth-eating habits of Elephants and Horses in India,” ‘Veterinarian,’ Oct., 1875.—Idem, “Further Remarks on Parasites from the Horse and Elephant, with a notice of new Amphistomes from the Ox,” ibid., Nov., 1875.—Diesing (l. c., in text).—Fitz, R. H., “Anatomy of Fasciola Jacksoni,” ‘Rep. of Boston Soc. Med. Sci.,’ in the ‘New York Med. Journ.,’ Nov., 1876.—Fleming, G., “The Diseases of Elephants” (chiefly from Captain Forsyth’s work on the ‘Highlands of Central India’), ‘Veterinarian,’ March, 1873, p. 181.—Mégnin, “Mém. sur les Hypopes,” in Robin’s ‘Journ. de l’Anat. et de la Physiol.,’ 1874 (H. elephantis), p. 248.—Ouchterlony, J. W., “An Essay on the Management of the Elephant, and its Treatment in ordinary Diseases,” ‘Rep. of Vet. Med. Assoc.,’ Nov., 1872, and pub. in ‘Veterinarian,’ Jan., 1873, p. 65.—Piaget, E., “Description d’un parasite de l’éléphant,” ‘Tijschrift voor Entomologie,’ 1869, p. 249.—Richter, H. C., “A new form of Parasite (Idolocoris elephantis),” ‘Science Gossip,’ 1871, pp. 131, 185, 211, 278.—Schmidt, Max, “Die Krankheiten der Dickhäuter,” ‘Deutsche Zeitschrift f. Thiermed. und vergleichende Pathologie,’ f. Nov., 1878, s. 360.—Williamson, T., ‘Oriental Field Sports,’ London, 1807, vol. i, p. 138.
The parasites of the Rhinoceridæ have been even less studied than those of elephants. In 1856 Prof. Peters described a tapeworm from Bruce’s rhinoceros (R. Africanus), which he named Tænia gigantea. In 1870 Dr Murie, under the provisional name of T. magna, published a description of the strobile of the same cestode from an Indian rhinoceros (R. unicornis). From a total misconception of the character of the proglottides, Murie was led to suppose that the segments of the strobile were very deep as well as broad; whereas the proglottids are remarkably narrow, thus partaking of the characters of the Tæniæ of the larger herbivora in general. In a subsequent paper Peters pointed out these errors. Murie had, in fact, rolled several segments into one. In 1877 Professor Garrod encountered the same cestode in Rhinoceros sondaicus, and, following Peters’ example, separated it from the Tæniæ proper (Plagiotænia gigantea). The idea of generically separating tapeworms possessing a more or less striking breadth of strobile is not one which commends itself to my view, seeing that many of the tapeworms of herbivora closely resemble the rhinoscerine cestodes in this respect. As Diesing hints, this tapeworm comes near to T. perfoliata, but Garrod’s and Peters’ figures both show that Plagiotænia wants the neck-lobes. The presence of cephalic appendages may be regarded as generically distinctive, but it does not appear that Blanchard separated the perfoliate tapeworm of the horse from the Tæniæ proper on this ground. Therefore, in my account of the equine tapeworms, I have not adopted his genus Anoplocephala. I may remark, in passing, that if the distinctions, as between armed and unarmed, or between proboscis-bearing (Rhynchotæniada) and non-proboscis-bearing tapeworms (Arhynchotæniada), are to be maintained, they should be expressive of divisional or subordinate value. Dr Weinland’s arrangement, having reference to the thick- and thin-shelled ova (Sclero- and Malaco-leptidota), is, perhaps, preferable. The whole subject of classification requires revision, but it should be undertaken by some helminthologists practically acquainted with a large number of cestode types. As Garrod has well observed, Plagiotænia enjoys a wide geographical distribution, infesting alike Indian and African hosts. Prof. Garrod, I observe, speaks of the head of the mature tapeworm as the scolex—an extension of the meaning of a term not usually recognised. In this, however, he only follows Peters’ unfortunate example.
The wide distribution enjoyed by Peters’ Plagiotænia is probably equalled by that of the rhinocerine stomach-bot (Gastrophilus rhinocerontis, Owen). This parasite was originally described in 1840, and since that time it has been frequently encountered both in India and Africa. To Mr Spooner Hart, of Calcutta, I am indebted for a large number of specimens; their size exceeding that of any other bots that have come under my notice. Probably this parasite infests the stomach of rhinoceroses generally; at all events, it occurs in R. unicornis, R. bicornis, and R. simus. At present the imago is unknown. The longest larvæ in my possession measure 11/8″, but Brauer records specimens up to 35 mm. in length by 10 mm. in thickness. In African hosts M. Delegorgue found these parasites in prodigious numbers.
Bibliography (No. 52).—Brauer, “Bot of the Rhinoceros,” ‘Monogr. der Œstr.,’ 1863, s. 92.—Cobbold, “Note on Parasites presented by Messrs Danford, Hart, and others,” ‘Veterinarian,’ 1875, p. 513.—Coquerel and Sallé, in ‘Ann. Soc. Entom. de France,’ 1862 (quoted by Brauer).—Delegorgue, ‘Voyage dans l’Afrique’ (quoted by Brauer).—Garrod, “On the Tænia of the Rhinoceros of the Sunderbunds (Plag. gig., Peters),” ‘Proc. Zool. Soc.,’ Nov. 20, 1877, p. 788.—Hope, in ‘Trans. Entom. Soc.,’ 1840, p. 259.—Joly, M. N., “Recherches Zool. (&c.) sur les Œstrides (&c.),” in ‘Ann. des Sciences (&c.) de Lyon,’ 1846 (quoted by Brauer).—Murie, J., “On a probably new species of Tænia (T. magna?) from the Rhinoceros,” ‘Proc. Zool. Soc.,’ 1870, p. 608.—Peters, W., “Note on the Tænia from the Rhinoceros, lately described by Dr J. Murie,” ‘Proc. Zool. Soc.,’ 1871, p. 146.
Very little has been written respecting the parasites of the Hippopotamidæ and Tapiridæ. I think it was Livingstone who first drew attention to the fact that the river-horse or sea-cow is much infested by tapeworms, but I have not seen any published description of the worm. Dr Murie, during his sojourn in Egypt, found a solitary bot embedded in the soft parts surrounding the eye, and judging from his figure the species is new to science. Provisionally I speak of it as the Hypoderma Muriei. In the paper (quoted below) Murie appends a list of all the animals in which bots have been found. Though chiefly taken from Brauer, it is useful and tolerably complete. So far as I am aware no cestodes have been described as infesting tapirs; nevertheless, at least five other kinds of helminth have been found in Tapirus Americanus. Of these, two are flukes (Amphistoma asperum and A. pyriforme), and three are nematodes (Sclerostoma monostechum, Spiroptera mediospiralis, and Sp. chrysoptera). The three species first named occupy the cæcum, whilst the others are found in the stomach. According to Molin’s description, both species occupy tuberous excrescences of the mucous membrane, thus reminding us of the similar habit enjoyed by Sp. megastoma in the horse. The Sp. chrysoptera is a comparatively large species, the males measuring an inch, and the females as much as an inch and a half in length. Both of the spiropteras were obtained from tapirs by the indefatigable Natterer, Sp. mediospiralis being also procured by him from the aguti. If I have read Molin correctly, as many as thirty-four examples of S. mediospiralis were taken from a single excrescence in the stomach of the tapir. Upwards of a hundred specimens were procured, collectively, from three similar stomach-excrescences in Dasyprocta aguti. These, and the other tapirine parasites above mentioned, were originally discovered in Brazil.
Bibliography (No. 53).—Diesing, “Neue Gattungen von Binnenwürmen nebst einem Nachtrage zur Monographie der Amphistomen,” in ‘Annalen d. Wien. Museums,’ Feb., 1839, s. 236.—Idem, ‘Systema,’ Bd. ii, s. 306.—Molin, “Una monografia del genere Spiroptera,” in ‘Sitzungsb. der math.-naturw. Cl. d. k. Akad. d. Wissensch.,’ Bd. xxxviii, s. 1001, 1859.—Murie, “On a larval Œstrus found in the Hippopotamus,” ‘Proc. Zool. Soc.,’ 1870, p. 78.