The next nematode of general interest is the pinworm (Oxyuris curvula). Professional men often confound it with the palisade worm, and it has even been mistaken for the rat-tail maggot (Helophilus). The longest males measure 13/4″, and the females often beyond 4 inches. This worm infests the colon in great numbers, the species being easily recognised by its long subulate tail. Like its much smaller congener infesting man, this worm occasions severe local irritation, clusters of the eggs often accumulating to form yellow incrustations at the verge of the anus. Equine pinworms are vegetable feeders, and, like human Oxyurides, are conveyed to the bearer in a direct manner. No horse properly looked after can be infested by these worms. Local washings and stable cleanliness being secured by an attentive groom, the animals are safe. Prophylactic measures of this kind are all-powerful against infection. Notwithstanding the ease, however, with which the oxyuris disorder may both be prevented and cured, we find it prevails extensively everywhere, alike in mankind and in solipeds. Dr Sonsino found these parasites abundant in Egypt, some of the worms reaching a length of nearly five inches (120 mm.). Mr Emmerson has given an interesting account of the prejudicial effects of these entozoa in the horses of Singapore.

One of the most remarkable equine parasites is that which I am in the habit of calling the large-mouthed maw-worm (Spiroptera megastoma), in contra-distinction to the small-mouthed species (S. microstoma). In this country the worm has attracted little notice, but through the kindness of Mr Spooner Hart, of Calcutta, and of Mr Percivall, of the 11th Hussars, stationed at Umballa, I have had abundant opportunities of examining this entozoon and the singular pathological appearances which it occasions. This parasite was first described by Rudolphi, who says:—“Spiroptera capitis discreti ore magno nudo, cauda feminæ rectiuscula acuta, mavis simpliciter spirali, corpusculis rotundis ad basim penis styliformis.” The worm was afterwards observed by Schultze, Chabert, and frequently also by Andral, but the best accounts of it are those given by Gurlt, Valenciennes, and Dujardin. Schneider has likewise done much to set at rest disputed points. Respecting the Spiroptère du Cheval, Dujardin, writing in 1844, observes that “Rudolphi at first studied this helminth from examples found in great number by Reckleben, at Berlin, in tubercles of the stomach of two horses. Quite recently, M. Valenciennes, at Paris, has found it frequently in tumours, from twenty to forty millimètres in size, in the stomach of eleven horses out of twenty-five that he had subjected to this kind of research. These tumours, lodged between the mucous and muscular layers of the digestive canal, are perforated by several holes traversing the mucous membrane. They are divided internally by a number of folds into numerous intercommunicating cavities, and sometimes filled with solid mucus and very many spiropteras. It is from examples collected by M. Valenciennes that I have been able to study the parasite.”

As regards the description of the worm, it is almost needless to say that Dujardin’s account is minute and admirable in all respects. In fact, no naturalist ever exceeded the Rennes savant in carefulness and accuracy of detail. An interesting point connected with these stomach-worms lies in the circumstance that Gurlt recognised two varieties, one of which he termed Sp. meg., var. major. It remained for Schneider to show that the larger worms formed an altogether distinct species, which he termed Filaria microstoma (‘Monogr.,’ l. c., 1866, s. 98). It was not unnatural that Rudolphi and his successors should confound these two forms together, and it is also not a little curious that the smaller of the two species has the larger mouth. Practically, veterinarians will probably rest content to know that whilst the Spiroptera megastoma occupies tumours in the walls of the stomach, the S. microstoma is always to be found free in the cavity of that organ. Any helminthologist who may chance to have read the Ceylon Company’s report on the fatal epidemic affecting the mules of the Mauritius in 1876 can scarcely fail to have observed that the worm called Ascaris vermicularis by Mr Bradshaw is none other than our Sp. megastoma. The description of the tumours as “reticulated” sufficiently explains their honeycomb-like appearance, but I think that the expression “alveolar” would better convey their true pathological character. Mr Spooner Hart compared these structures, which he terms “abodes,” to mole-hills, but there is no good ground for supposing that the wanderings of the parasites are in any sense comparable to the burrowings of the mole. In like manner the expression “nidus,” employed by Mr Bradshaw, though suggestive of their nest-like appearance, is to some extent misleading, as it implies that the worms form a nide or brood. Possibly, it may turn out that all the nematodes in each tumour have been bred in the spot where they are found, but hitherto they have only been seen in the adult state. Earlier stages of growth should be diligently sought for. Widely dissimilar as the two maw-worms are, it would not greatly surprise me to learn that Sp. megastoma and S. microstoma are dimorphic conditions of one and the same entozoon. At all events, Ercolani’s determination of the relations subsisting between Ascaris inflexa and A. vesicularis suggests a possible analogy of this kind. I may mention that the male Spiroptera megastoma reaches nearly one third and the female one half of an inch in length. A constriction separates the head from the body. The mouth is surrounded by four thick horny lips, the dorso-ventral pair being the larger. The tail of the male is spirally twisted, and furnished with lateral bands supported by three or four ribs. It carries two curved spicules of unequal size. There are five pairs of caudal papillæ, the tail being bluntly pointed in both sexes. The vulva of the female is placed about 1/7″ below the head. The eggs are linear or very narrow, and furnished with thick shells. According to Sonsino, who found Sp. megastoma in five out of sixteen Egyptian horses, the verminiferous growths are usually seated near the pyloric end of the stomach, as many as four tumours occurring at one time. Neither Sonsino nor any other observers already quoted appear to think that these morbid changes in any way interfere with the healthy performance of the gastric functions. However, I am of opinion that at least one recorded fatal case of parasitism, producing rupture of the stomach, affords an instance, however rare, of the injurious action of this entozoon. It is reported under the signature of “Argus,” quoted below.

In this connection I may mention that in 1864 Prof. Axe observed some small worms, scarcely visible to the naked eye, in the mucous membrane of the stomach of a donkey, the same worms being subsequently observed in three other donkeys brought to the dissecting room of the Royal Veterinary College. From the examination of a drawing of one of the male worms, executed by Prof. Simonds, I am led to believe that the parasites are entirely new to science. The hood being well marked there can be no doubt as to the strongyloid affinities of the worm. I therefore propose to call the worm after its discoverer (Strongylus Axei).

In regard to Sp. microstoma, the males measure up to 2/3″, whilst the females have a long diameter of 3/4″ or rather more (10‴). The small-mouthed maw-worm lives free in the stomach, and, as Krabbe observes, not unfrequently in very considerable numbers. It does not appear to be capable of injuring the host.

One of the most interesting equine nematodes is the eye-worm. Most veterinary writers speak of it as the Filaria oculi, but to helminthologists it is better known by the more correct designation, F. papillosa. Though commonly obtained from the eyeball and its tunics, the worm infests various tissues and organs of the body, being found in the thorax, abdomen, membranes of the brain, muscles, and cellular tissues. It infests the ass and mule, and also horned ruminants. The males attain a length of three inches and the females seven inches. The head is broad, with a gaping mouth armed with a ring of chitine and two prominent denticles. There are also two papillæ on the neck near the middle line, besides sixteen caudal papillæ, eight on either side. The tail of the male is spirally twisted, that of the female only slightly curved. Notwithstanding the many opportunities afforded of examining this parasite in the fresh state, very little is known respecting its origin and course of development. Dr Manson, who found that the mouth was armed with a five- or six-toothed oral saw, considers that the eye is not a proper resting place for the parasite, and that when one wandering worm comes across the track of another it follows it up from sexual instinct, and thus several may be found together in one place. The tracks are readily seen by the naked eye. Dr Sonsino speaks of it as a “yellow line.” This Italian observer found the worm in twelve out of the sixteen solipeds he examined during the plague. Each horse showed from two to a dozen worms “in the peritoneal cavity, wandering free on the serous lining, without causing any apparent mischief to the membrane.” On one occasion Sonsino found the worm in the liver. From the similarity of habit there can be little doubt that the cases of guinea-worm (F. medinensis) recorded by Clarkson and others, as occurring in the horse, were merely examples of F. papillosa. I think so all the more because the lamented Fedschenko verbally expressed to me his astonishment that I had in my introductory treatise (p. 387) spoken of the Dracunculus as an equine parasite. I did so on the authority of others. To the Rev. Horace Waller I am indebted for specimens of the eye-worm brought from Assam, and to Mr Spooner Hart for others sent from India. For examples occurring in England I am indebted to Mr Haydon Leggett, who, in 1875, sent me three specimens extracted from the eye of a five-year-old mare. Mr Steel has also given me an example of F. papillosa taken from the peritoneum of a donkey. Similar cases are constantly occurring in the practice of veterinarians in Hindostan. Highly interesting Indian cases are recorded by Kennedy, Molyneux, Twining, and Breton, and in addition to these I may also particularise those of Macnamara, C. Percivall, Hickman, Clarkson, Skeavington, and Jeaffreson. The cases by Lee and Grellier also deserve attention.

Another species of thread-worm (Filaria lacrymalis) is occasionally found in the horse between the lids and eyeball. It is a comparatively small and harmless parasite, the males measuring 1/2″ in length and the females 2/3″. It also infests the ox. Both the large and small eye-worms are viviparous, and, not improbably, both of them are the means of conveying embryonic Filariæ into the circulation. Be this as it may, we owe to Dr Sonsino the discovery of hæmatozoa in an Egyptian horse. The larval worm was provisionally named by him Filaria sanguinis equi. The microscopic nematodes closely resemble the larvæ of F. sanguinis hominis, but they are smaller. The horse from whose blood Dr Sonsino obtained the minute worms was also found, by post-mortem examination, to have been infested by Filaria papillosa, a circumstance which naturally suggested a genetic relation between the larval and adult parasites. Similar, if not the same, microscopic worms had been previously discovered by Wedl, who primarily and independently regarded them as embryos of F. papillosa. Another curious filaria-like entozoon is the reticulated threadworm (Onchocerca reticulata). In England we have no acquaintance with this singular parasite, but it appears to be tolerably common in Italy. Excellent figures of it have been given by Diesing. Both males and females are in the habit of coiling themselves within the muscles, where they are found invested by a capsule of connective tissue. When unrolled the sexes are found of equal size, acquiring a length of 11/2″. The worm has a simple unarmed mouth, its body being marked by a series of annulations formed of incompletely anastomosing rings. It does not appear to possess any clinical importance.

In connection with the equine nematodes I need only mention the lung-worm (Strongylus micrurus). Its importance in relation to the production of husk or parasitic bronchitis in calves has already been considered. The worm is rarely productive of mischief amongst solipeds, nevertheless, in the dissecting-room subjects at the Royal Veterinary College, the presence of these parasites in the lungs is frequently noticed. Lastly, it only remains for me to observe that the renal strongyle (S. gigas) is occasionally seen in the horse. In 1792 M. Chabert found one in the left kidney, and similar cases have since either been witnessed or reported by Rudolphi and Leblanc.

Of the numerous insect parasites and tormentors of solipeds the gadflies (Œstridæ) demand chief attention. For special description of the forms, Brauer’s monograph is the most, and, in fact, the only reliable authority. Here it is not possible to give the characters of the various equine species, of which at least half a dozen are known to science. As remarked by me in the special chapter contributed to Prof. Williams’ well-known veterinary treatise, the common gad-fly (Gastrophilus equi) attacks the animal whilst grazing late in the summer, its object being, not to derive sustenance, but to deposit its eggs. This it accomplishes by means of a glutinous excretion, causing the ova to adhere to the hairs. The parts selected are chiefly those of the shoulder, base of the neck, and inner part of the fore legs, especially about the knees, for in these situations the horse will have no difficulty in reaching the ova with its tongue. When the animal licks those parts of the coat where the eggs have been placed, the moisture of the tongue, aided by warmth, hatches the ova, and in something less than three weeks from the time of the deposition of the eggs, the larvæ make their escape. As maggots they are next transferred to the mouth, and ultimately to the stomach along with food and drink. A great many larvæ perish during this passive mode of immigration, some being dropped from the mouth, and others being crushed in the fodder during mastication. It has been calculated that out of the many hundreds of eggs deposited on a single horse, scarcely one out of fifty of the larvæ arrive within the stomach. Notwithstanding this waste the interior of the stomach may become completely covered with “bots.” Whether there be few or many, they are anchored in this situation chiefly by means of two large cephalic hooks. After the bots have attained perfect growth they voluntarily loosen their hold, and allow themselves to be carried along the alimentary canal until they escape with the fæces. Many persons suppose that during their passage through the intestinal canal they re-attach themselves to the mucous membrane, thereby occasioning severe intestinal irritation. This is an error. In all cases they sooner or later fall to the ground, and when transferred to the soil they bury themselves beneath the surface, in order to undergo transformation into the pupa condition. Having remained in the earth for a period of six or seven weeks they finally emerge from their pupal-cocoons as perfect dipterous insects. It thus appears that bots ordinarily pass about eight months of their lifetime in the digestive organs of the horse.

That they are capable of giving rise to severe disease there can be no doubt, but it is not often that the disorder is correctly diagnosed, since it is only by the passage of the larvæ that the practitioner can be made aware of their presence. Mr J. S. Wood has published a case of tetanus in a mare, associated with the larvæ of Œstrus equi, and Mr J. T. Brewer has also given a case where the duodenum was perforated by bots. Mr Goodworth records an instance of pyloric obstruction from the same cause, and Mr W. Coupe informed me in 1876 that he had a drove of foreign ponies under his care, all of which suffered irritation from hæmorrhoidal bots. He removed them with a pair of forceps. Although frequently said to do so, the common bot does not attach itself to the rectum before finally escaping the host. The larvæ of G. hæmorrhoidalis normally reside there. In this situation they seriously inconvenience the bearer. The bots of G. nasalis are often confounded with those which ordinarily occupy the stomach of the bearer. The larvæ of G. nasalis commonly reside in the duodenum near the pylorus. According to Schwab and Brauer, they rarely occupy the stomach. As occurs in the common species, this bot passes away with the fæces, and does not attach itself to the lower bowel. The bots of Brauer’s G. inermis much resemble those of G. equi, but they are much smaller and attach themselves to the wall of the small intestine. The bots of G. pecorum, which dwell in the rectum, are readily recognised by their peculiar form and scanty spination. They are pointed in front and truncated posteriorly. An assinine variety of G. equi has been described by Bilharz, whilst another distinct species (G. flavipes) attacks the ass and mule. The bot-larvæ of the latter host require recognition and description. A great variety of other equine bot-flies have been described, but all, or nearly all, of them are mere synonyms of the above-mentioned forms. For the limitation of the species I accept Brauer’s authority, and likewise his nomenclature. A great deal of nonsense has been written respecting bots. It is a relief to believe that G. (Œstrus) veterinus, G. ferruginatus, G. jubarum, G. (Œ.) Clarkii, G. salutiferus, G. subjacens, and many others, are not good species, at least that they are mere synonyms. In regard to the occurrence of subcutaneous bot-like maggots in the horse and ass, no doubt need exist on this point. I am indebted to Mr Percy Gregory for characteristic specimens taken from the back, neck, and withers of a four-year-old gelding. They appear to correspond with the Hypoderma Loiseti of Joly. Similar maggots have been found in the ass by Herr Erber, but Brauer refers these to H. silenus. Prof. Brückmüller published a case where the brain was infested by larvæ; and Mr Shipley has sent me an example of H. equi, which he states he removed from the choroid plexus of the brain. In addition to the cases by Woods, Goodworth, and Brewer, already quoted, others have been published by Tyndal and Cartwright.

Amongst the numerous other parasitic dipterous larvæ one must notice the rat-tailed maggots (Helophilus). A genuine instance of this kind has been brought under my observation, but the example recorded by Professor Axe was spurious. Professor Simonds and myself saw this supposed maggot, which was merely a very stout and pregnant Oxyuris curvula. Another genuine case was published by Mr. Stanley. This is quoted by A. Numan in his essay on Cœnurus. I have previously mentioned my having received an Helophilus-larva that had passed from the human body. One of the most troublesome external parasites is the so-called horse-tick or forest-fly (Hippobosca equina). They attack the abdomen, flanks, and inner part of the thighs in great numbers, occasioning great distress to the bearer. Being of leathery toughness their bodies are not easily crushed, and they are removed only with great difficulty. There is an equine disease in Sweden called Stackra, which is erroneously attributed to injuries produced by a species of fly-maggot (Lixus) which lives on the fine-leaved water-drop wort (Phellandrium). As regards the so-called free parasites, or rather non-parasitic obnoxious insects, which torment solipeds, it is impossible even to enumerate them. The tsetse of South Africa (Glossina morsitans) is terribly fatal to the horse, but it is said that the mule, ass, and zebra do not suffer from its bites—an immunity shared by swine, goats, antelopes, and man himself. Major Vardon’s rash experiment (based on the supposition that horses deprived of fresh green food would not suffer from the attacks of the fly) proved fatal to an animal which he purposely exposed on a much infested hill-top. The horse died ten days after it was bitten. According to Chapman, the bites of four tsetse flies are sufficient to kill an ox, but in man the irritation produced is very slight. Amongst other insects proving troublesome to solipeds may be mentioned the leg-sticker (Stomoxys calcitrans), the clegg (Hæmatopota pluvialis) which is very abundant in the West Highlands, various species of Tabanidæ and Asilidæ (Tabanus autumnalis, T. bovinus, Chrysops cæcutiens, Asilus crabroniformis), and also a host of ordinary flies and gnats (Muscidæ and Tipulidæ), as, for example, Anthomyia meteorica and Culex equinus. In India the bite of a species of Simulia gives rise to the formation of open sores of the most intractable character. As regards hemipterous insects it may be said that many species of lice (Anoplura) produce what is called phthiriasis or lousiness in the horse, some of them being derived from poultry. The best known species are Trichodectes equi, T. scalaris, Hæmatopinus equi, H. vituli, H. eurysternus, and the ass-louse (H. asini). Of the half dozen or more species infesting the hen (belonging to the genera Goniocotes, Liotheum, &c.) it is not probable that more than one or, at most, two of them are concerned in the production of poultry-lousiness in the horse. As an equine disorder this kind of phthiriasis was first described by Bouley. Cases in England have been observed by Messrs. Henderson, Moore, and Woodger. For some account of cases of lousiness due to Hæmatopinus I am indebted to Mr S. Butters. As regards the scab, itch, and mange insects or mites (Acaridæ), three perfectly distinct forms are known. Adopting M. Mégnin’s classification they are Sarcoptes scabiei, var. equi, Psoroptes longirostris, var. equi (being the Dermatodectes equi of Gerlach), and Chorioptes spathiferus, var. equi, which is the Symbiotes equi of Gerlach. All the species have been beautifully illustrated by M. Mégnin, whose memoir has dispersed many of the clouds of error and misrepresentation which have hitherto surrounded the subject. Whilst Psoroptes forms the true horse-mite, and attacks various parts of the body, Chorioptes confines its attacks to the posterior regions. Messrs South and Day and myself have verified some of the facts recorded by Mégnin in respect of the structure and habits of this last species. Another kind of mite (Glyciphagus hippopodos) is stated to infest the ulcerated feet of horses. It would appear that no true ticks properly belong to solipeds; nevertheless, the common cattle-tick (Ixodes bovis) occasionally attacks horses. Probably several other species of Ixodidæ, known to infest other animals, behave in the same way. The Arachnidan called Pentastoma tænioides, though properly belonging to the dog, has on several occasions been detected in the nasal or frontal sinuses of the horse. Such instances are recorded by Chabert and Greve. The largest example of this singular entozoon seen by myself was obtained from the same situation, and presented to me by the late Mr C. B. Rose, whose writings I have frequently quoted in connection with the Cœnuri of rabbits.

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Rev.,’ July, 1858.—Goodworth, S., “Obstruction of the Pyloric Orifice of the Stomach by Bots,” ‘Veterinarian,’ p. 410, 1837.—Grellier, J., “On the Worm in the Eye (of the Horse),” ‘Veterinarian,’ p. 18, 1844.—Harlan, R., “Case of a Colt killed by Worms,” in his ‘Med. and Phys. Researches,’ p. 554; see also ‘Med.-Chir. Rev.,’ 1836.—Harris, “A Case of Worms in the Arteries of a Colt,” ‘Veterinarian,’ p. 307, 1834.—Harrison, J. D., “The singular effect of Worms in the Stomach of a Mare,” ‘Veterinarian,’ p. 331, 1842.—Hickman, T., “Worm in the Eye of the Horse,” ‘Edin. Vet. Rev.,’ 1864, p. 653.—Hopkinson, F., “Account of a Worm in the Horse’s Eye,” from ‘Trans. of Amer. Phil. Soc.,’ in ‘Med. Comment.,’ vol. xi, p. 166, 1784.—Hutchinson, J., “Hydatid in the Eye of a Horse,” ‘Path. Soc. Trans.,’ and rep. in ‘Lancet,’ 1857.—Huxley, “On Echinococcus (from the Zebra),” see Bibl. No. 20, o.—Jeaffreson, W., “Case of Removal of a Worm from the Eye of an Arab Horse,” ‘Lancet,’ p. 690, 1836–37, and ‘Veterinarian,’ p. 471, 1837.—Kennedy, M., “Account of a Nondescript Worm (Ascaris pellucidus) found in the Eyes of Horses in India,” ‘Trans. Roy. Soc. Edin.,’ vol. xi, p. 107, 1816.—Kirkman, ‘Hydatids’ (see Bibl. No. 20, o).—Knox, ‘Edin. Med. and Surg. Journ.,’ 1836.—Krabbe (l. c., in text).—Lee, C. A., “On Filaria papillosa in the Anterior Chamber of the Eye of a Horse (and on Filariæ in general, &c.),” ‘Amer. Journ. Sci. and Art.,’ vol. xxxix, p. 278, 1840.—Lessona, G., “On the Bot (or Œstrus) of the Horse,” from ‘Recueil de Méd. Vét.,’ in ‘Veterinarian,’ p. 156, 1854.—Leuckart (l. c., in text).—Litt, W., “A Singular Case (of an immense number of Worms in a Colt),” ‘Veterinarian,’ p. 529, 1852.—Macnamara, “On F. papillosa in the Eye of Man and the Horse,” ‘Indian Ann. Med. Sci.,’ 1864.—Marcet (see Bibl. No. 34).—Mead, J., “A Worm in the Scrotum of a Colt,” ‘Veterinarian,’ 1843, p. 648.—Mégnin, “Petit Tænia inorme du Cheval,” in ‘Bull. de la Soc. Cent. de Méd. Vét.,’ t. vi, 3e série, p. 112.—Idem, ‘Monog. de la tribu des Sarcoptides,’ &c.; see also review by myself in the ‘Veterinarian,’ Aug., 1877.—Mercer, J., “On Entozoal or Worm-aneurism,” ‘Lond. Med. Gaz.,’ 1847, and in part x of “Contrib. to Zool. Path.,” in the ‘Veterinarian,’ p. 33, 1846.—Meyrick, J., “Death of a Colt from Entozoa within the Abdomen,” ‘Veterinarian,’ 1859, p. 695.—Moir, J., “Rupture of the Ileum resulting from Worms,” ‘Veterinarian,’ 1857, p. 265.—Molyneux, R., “On Worm in the Eye of Horses in India,” ‘Veterinarian,’ 1828, p. 309.—Morgan, A., “Case of Hydatid in the Brain of a Mare,” ‘Veterinarian,’ p. 396, 1855.—Numan, A., ‘Ueber die Bremsen Larven, im Magen der Pferde,’ 1837.—Idem, “Entozoon (Monostoma settenii) from the Eye of a Horse,” from ‘Tidschr. voor naturl. Geschied. en Physiol.,’ 1842, in ‘Med.-Chir. Rev.,’ 1842.—Idem (for remarks on Cysticercus fistularis), ‘Over den veelkop blaasworm’ (l. c., Bibl. No. 49), p. 263.—Peall, T., “A Discourse on ‘Worms,’” at p. 37, in his ‘Observations, chiefly practical, on some of the more common Diseases of the Horse,’ pub. at Cork, 1814.—Percivall, C., “Worm in the Eye of the Horse (two cases),” ‘Veterinarian,’ p. 75, 1828.—Percivall, J., “A Case of Ascarides in the large Intestines of the Horse,” ‘Veterinarian,’ p. 358, 1829.—Poulton, T. J., “Large numbers of Parasites in the Intestines of a Mare,” ‘Veterinarian,’ 1866, p. 385.—Seaman, J., “Worms in the Blood-vessels of Horses and Colts,” ‘Edin. Vet. Rev.,’ 1864, p. 520.—Simonds, “On Disease of the Mesenteric Artery, produced by Strongyli,” ‘Path. Soc. Trans.,’ 1854.—Skeavington, G., “On Worm in the Eye of the Horse (three cases),” ‘Veterinarian,’ 1834, p. 196.—Sonsino, P., “On the Entozoa of the Horse in relation to the late Egyptian Equine Plague,” ‘Veterinarian,’ Feb. and March, 1877.—Tyndal, J., “Worms in the Intestines of a Mare,” ‘Veterinarian,’ 1843, p. 629.—Twining, W., “Obs. on the Filaria or Threadworm found in the Eyes of Horses in India,” ‘Calcutta Med. and Phys. Soc. Trans.,’ vol. i, p. 345, 1825; rep. in ‘Veterinarian,’ p. 114, 1828.—Valenciennes, “On the Spiroptera megastoma of Gurlt,” abstract of a paper from Acad. Sci. of Paris, reported in ‘Lancet,’ 1843.—Varnell, “Remarks on Cases of Parasitic Disease in Horses,” ‘Veterinarian,’ p. 201, 1864.—Veret, “Perforation of the small Intestines by Ascarides lumbricoides (in the Horse),” from ‘Rec. de Méd. Vét.,’ in ‘Veterinarian,’ p. 569, 1837.—Vincent, “Curious case of Incurable Lameness from Hydatids,” ‘Veterinarian,’ 1848, p. 674; see also p. 3, ibid.—Wallis, “Note on the occurrence of (250) Lumbrici in a Horse,” ‘Veterinary Record,’ 1849, p. 300.—Walters, R. G., “Parasites in the Kidneys of a Mare,” ‘Veterinarian,’ 1866, p. 265.—Woodger, “Hydatid in the Brain of a Horse,” ‘Veterinarian,’ 1863, p. 75.—Woods, J. S., “Tetanus in a Mare, associated with the Larvæ of Œstrus equi within the Stomach and Duodenum,” ‘Veterinarian,’ 1859, p. 693.—Wright, “Strongyli in the Scrotum of a Colt,” ‘Veterinary Record,’ 1849, p. 385.—Youatt, “Worms between the Tunics of the Stomach,” ‘Veterinarian,’ 1835, p. 571.—Idem, “Tetanus, Worms in the Trachea, and Dilatation of the Heart, in a Zebra,” ibid., p. 504, 1836.—Idem, “Worms in the Nasal Cavity of the Horse,” ibid., p. 329, 1832.—Zangger, “Remarks on Entozoa,” from the French, ‘Veterinarian,’ 1855, p. 463.

Part X (Pachydermata)

At the Norwich Meeting of the British Association, in 1868, I exhibited two flukes received from J. S. Thacker, V.S., of the Madras Army. They were handed to me by the late Dr Baird, and were labelled “Distoma taken from liver of elephant and forwarded for classification.” I stated at the time that these entozoa were identical with certain flukes previously obtained from the duodenum and biliary ducts of an Indian elephant, and which, though carefully preserved in the Boston Museum, U.S., had never been properly described. They were only briefly noticed by Dr Jackson in his ‘Descriptive Catalogue’ of the Museum. In the summer of 1868 fifteen specimens of fluke, removed from Burmese elephants, had been forwarded to and received by Professor Huxley from Rangoon, accompanied by a statement to the effect that they were the cause of an extensive and fatal disease in Burmah. Through the kindness of Prof. Huxley I was allowed to make use of his specimens for the purpose of comparison and identification, and thus it became evident that our specimens were of the same species. It was also evident that the species could be none other than that represented by the Boston specimens. Further examination having made it clear that the organisation of these flukes departed from the ordinary distome type, I named the parasite Fasciola Jacksoni, at the same time offering the following description (‘Entozoa,’ Supp., 1869, p. 80):—“Body armed throughout with minute spines, orbicular, usually folded at either end towards the ventral aspect, thus presenting a concavo-convex form; oral sucker terminal, with reproductive papillæ about midway between it and the ventral acetabulum; intromittent organ 1/4″ in length; digestive apparatus with two main zigzag-shaped canals, giving off alternating branches at the angles thus formed, the ultimate cæcal ramifications occupying the whole extent of the body; length, when unrolled, from 1/2″ to 5/8″, breadth 1/3″ to 1/2″.” Now, if reference be made to the appendix of the late C. M. Diesing’s ‘Systema Helminthum,’ it will be found that Jackson’s statement had not escaped that helminthologist’s notice, though, not having seen any specimens, he was not unnaturally led to place the species amongst the distomes proper. In Diesing’s subsequently published ‘Revision der Myzelminthen,’ the species is formally characterised as the Distomum elephantis of Jackson (‘Sitzungsberichte d. Math.-nat. Cl. d. k. Akad. d. Wissenchaften,’ Bd. xxxii, 1858). In my “Synopsis of the Distomidæ,” which appeared in the ‘Journal of the Linnean Society’ for 1861, I had also placed it amongst the distomes, not considering it to be a doubtful form (‘Proceed. Linn. Soc.,’ “Zoology,” vol. v, p. 9). These references exhausted the literature of the subject up to the time of the issue of my ‘Manual’ in 1873, where this fluke is again briefly noticed (p. 13). Several of Prof. Huxley’s specimens have been added to the entozoological department of the Hunterian Museum. It is clear that all these notices and descriptions point to the same parasite. The worm has since been more carefully described by Dr R. H. Fitz, from a series of dissections and preparations made by Dr H. P. Quincy, and deposited in the Warren Museum, Boston, U.S.

About the middle of June, 1875, I received a letter from General Hawkes, of the Madras Staff Corps, dated Secunderabad, May 12th, 1875, and in reference to the subject before us he writes as follows:—“My attention has been recently directed to a very unusual mortality of elephants at this station. Out of twenty-eight elephants under my charge, no less than twelve have died within the last sixteen months, whereas the average annual mortality has been hitherto only two per annum out of thirty-eight in our establishment. In every case of death there appeared to exist serious organic disease quite sufficient to account for such death, but as the mortality increased I had a post-mortem examination made in each case; and although here also organic disease sufficient to account for death was present in each case, yet in every one of these elephants we found the liver-fluke in greater or less abundance.” General Hawkes adds:—“Meanwhile I have sent you a small box containing three bottles, one containing the liver-fluke (Fasciola Jacksoni) referred to in your work on the parasites of domesticated animals. It seems possible that the other two species of parasites may not have been brought to your notice. Both of these, namely, the “masuri” and the “soorti,” are very common in elephants. They are both found in the intestines only. The “masuri,” when present in any quantity, cause considerable disturbance, and the animal instinctively resorts to the eating of earth, which it consumes in large quantities until the bowels are acted on and the worm expelled. The soorti is more common than masuri, and does not seem to inconvenience the animal very much. When expelled from the animal the soorti is a round white worm, like most of the threadworms; the masuri, on the other hand, is of a delicate flesh color.” Shortly after the receipt of this letter I obtained the entozoa in a good state of preservation. Accordingly I wrote to General Hawkes, stating that the flukes were clearly referable to Fasciola Jacksoni; that the parasites to which the natives of Hindostan apply the term “soorti” were evidently examples of Ascaris lonchoptera (Diesing), previously called strongyles by Rudolphi; and that the worms which he called “masuri” were trematodes new to science. I named the species Amphistoma Hawkesii, in honor of the donor. The bottle contained as many as forty-nine specimens. I may here remark that I have made inquiries of the keepers of the elephants at the Zoological Gardens as to whether they have ever seen entozoa that were passed by the animals under their care. They replied in the negative, the keeper of the African elephants (Scott) having made frequent inspection of the fæces. I was the more anxious to secure information on this point since, during my frequent visits to the menagerie, I had observed that the African elephants were in the habit of swallowing large quantities of mud and dirt from small hollows in the ground near the great water-tanks in which they bathe. Prof. Garrod (who had dissected three elephants) also assures me that there has been no trace of an entozoon in any of the Indian elephants examined by him. In one dissected at Edinburgh the same negative result was obtained. From the facts at present in my possession, I conclude that the habit of earth-eating, displayed alike by Indian and African elephants (and, as stated in my account of the equine parasites, shared by horses), is not necessarily due to the presence of parasites. I apprehend rather, that it is resorted to by these animals under any circumstances of intestinal irritation, whether created by entozoa or other foreign agents. The notion of the elephant’s intelligent self-cure by eating earth is a very old fable. Captain Forsyth, as quoted by Mr Fleming, alludes to it in his ‘Highlands of Central India,’ and I find the same ideas recorded by Williamson and Howitt. Forsyth says:—“Elephants are very liable to intestinal worms. They generally cure themselves by swallowing from ten to twenty pounds of earth.” Captain Williamson says:—“They are much troubled with worms, for the cure of which the elephant eats earth. If the dung be inspected there will be seen an amazing number of moving objects, which much resemble pieces of chewed sugar-cane.” Some excellent practical remarks are added, testifying to the value of the native remedy called Kallah-nimok, or bit-noben, which is a saline purgative. In Lieut. Ouchterlony’s essay (quoted below) no allusion is made to the subject of worms.

General Hawkes afterwards supplied me with further information. In a letter from Secunderabad, dated July 30th, 1875, he says:—“As regards the liver-fluke (F. Jacksoni), it appears from your treatise to have been first observed in 1847. The only other published notice that I have been able to find of it is contained in a letter to a newspaper, dated ‘Rangoon, 16th July, 1867,’ and is signed ‘R. B.’ In this letter the unusual mortality of seven elephants in about fifteen days is attributed to the presence of this liver-fluke, the two other parasites (Amphistoma and Ascaris lonchoptera) being also present in the intestines.” “Now (continues General Hawkes), in every case at which I was present flukes were found in greater or less numbers in the gall-ducts of the liver, and the Amphistoma was also as constantly present in the intestines, the soorti (Ascaris lonchoptera), contrary to the general experience of the elephant attendants, being less frequently met with, though from its color and slender shape it is not so easily detected among the huge mass of fæces as the larger Amphistoma.” Speaking of the amphistoma General Hawkes says:—“This internal parasite is well known to all who possess elephants. It is alluded to by Dr Gilchrist in his treatise on the ‘Diseases of Elephants,’ first published in 1841, but he merely mentioned it under its local name, masuri, and made no attempt either to describe it scientifically or to ascertain its place in the natural system. As far as my experience goes it is only found in the intestines. These parasites appear to be very generally present in the elephant. When their numbers are few the ‘host’ is probably not much inconvenienced, but when present in any great quantity they undoubtedly cause much irritation. When this is felt, the animal, as before remarked, instinctively resorts to a simple and effectual remedy. He eats a quantity of earth, which purges him thoroughly and expels the amphistoma. The mahawats are of opinion that whilst the elephant is eating earth to relieve himself of the pests the daily allowance of rice should be scrupulously withheld; and they say that if the rice, which is given uncooked, is eaten by the animal under these circumstances, excessive purgation is induced, which frequently results in death. How far this opinion is founded on fact I am unable to say, but the mahawat’s name for this disease means ‘fasting,’ and bears testimony to the generally received notion of the necessity of withholding the rice when the animal is eating earth.”

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.

The osculant position of the anisodactyle pachyderms (Hyracidæ), formerly classed as rodents, renders it desirable that their parasites should be briefly noticed in this place. Probably these animals, zoologically speaking, come nearest to the rhinoceroses, but Prof. Owen showed that, anatomically, they possessed marked affinities with the sloths. The klipdas or dasse (Hyrax capensis) is infested by a tapeworm, of which hitherto the proglottides only appear to have been seen (Tænia hyracis, Pallas). Under the name of Cœnurus serialis a larval cestode has been described by Gervais, the same parasite being called Arhynchotænia critica by Pagenstecher (“Zur Naturgeschichte der Cestoden,” in ‘Sieb. u. Köll. Zeitschrift’). A variety of nematodes have also been observed in the Cape hyrax. Of these, the so-called Physaloptera spirula is classed as doubtful by Molin and Diesing. Hemprich and Ehrenberg furnished brief descriptions of four other nematodes. Two of these worms were placed in the genus Oxyuris (O. pugio and O. flavellum), and the other two in the new genus Crossophorus, which they formed for their reception (C. collaris and C. tentaculatus). The whole of these nematoids were obtained either from the cæcum or large intestine.

An able article in the ‘Natural History Review’ for July 1865, attributed to Professor Huxley, expressed very clearly the popular notion as to the great danger of the flesh of swine considered as a source of human parasites. No doubt the filthy pachyderms in question (Suidæ) are much infested by helminths, some of which gain access to man, but swine are neither attacked by a greater variety of entozoa than other domesticated animals, nor are they so frequently a source of human tapeworms as cattle. In the article above quoted the following passage occurs:—“Of all animals, feral or domestic, the common pig is beyond all doubt the most fertile source of human entozoa; at least, of important parasites, Trichina spiralis and the tapeworm would, there is good reason to believe, cease to infest us, did not this favorite quadruped act the part of a communicating medium.” This paragraph was evidently written under the impression that “the tapeworm” most commonly found in man was derived from the hog. So far back as 1864 I showed that this was an entire mistake.