| OCR Text |
Show 1876.] DR. T. s. C O B B O L D O N E N T O Z O A . 295 Zoological Gardens. Some of these have been described in the Society's 'Proceedings ;' and others have been publicly noticed elsewhere in a less formal manner. Amongst the series in question was a bottle that contained three different species of nematoid parasites, all derived from one and the same host. The infested animal was a Lemur (Pithecia leucocephala) which appears to have died at the Gardens on the 28th of June, 1866. The worms were of three well-marked sizes. The largest species, represented by a single parasite and measuring 8| inches long, could not be distinguished from the ordinary Ascaris lumbricoides of the human subject. It had been removed by Dr. Murie from the rectum. The worms of intermediate size, numbering in all eleven specimens, were taken from the stomach and oesophagus; six of these were males averaging from an inch to an inch and a quarter in length. The five females varied from 1-j" to 2" in length. A pocket-lens examination at first suggested that they were examples of Spiroptera dilatata (a species that is common in the South-American Monkeys) ; but I have since determined otherwise. The smallest set of parasitic worms from the Lemur, of which there were no less than forty-four specimens in the bottle, proved to be new to science. These had been removed from the small intestine. In the condition in which I received them they were each thrice or four times coiled upon themselves, reminding one of the appearance so often seen in the encapsuled nematodes of fishes. After m y original brief examinations, I put all the worms aside for future study ; and it was not until the 16th of April, 1873, that I found the necessary leisure to work out the general structure of these elegant little parasites. Their minute size rendered them eminently favourable for microscopic examination; and in this way I obtained evidence of the existence of several peculiarities that I had not hitherto encountered amongst the nematodes. The following characters will form a ready means of identification:-Head well marked and furnished with a transversely striated bilateral membrane which projects beyond and contributes to the formation of the mouth; oral aperture simple and continuous with a long and moderately narrow oesophagus ; body decidedly attenuated in front and almost uniformly thickened behind, its surface being marked by 12 or 14 conspicuous lines, forming in profile slightly raised parallel ridges extending from one end to the other; tail of the female suddenly narrowed to a conical point, the arms being placed within a very short distance of its extremity; tail of the male furnished with a large circular and apparently undivided hood, supported by ten rays; spicule solitary and rather long. Males only -i-, and females only i; of an inch in length. In addition to the above diagnosis I may add that I have named the species hemicolor, from the circumstance that the anterior half of the body in nearly all the specimens was a shade darker in colour than the posterior half. I have illustrated the structure of the worm by five figures. One of these affords a general view of the male parasite naturally coiled upon itself (Plate XXI. fig. 5). The longitu- |
