170 LEUCKART, ON TRICHINA SPIRALIS. 



conical eminences placed on either side of the genital orifice, 

 and much resembling the well-known conformation of the 

 •genus Protecosacter. Spicule are everywhere present, but of 

 extreme delicacy. 



The Trichinae above described are, as is obvious at a glance 

 (and as is shown more especially by the presence of the 

 embryos in the female), full-grown. Moreover, there can be 

 no doubt that they do not undergo any further metamorphosis 

 (into Trichocephalus or Strongylus, &c.) 



Notwithstanding the vast numbers in which they occurred 

 in the animals examined, and in which they must exist in 

 other cases, these nematodes have hitherto escaped the notice 

 of helminthologists. The generic appellation of Trichina 

 might be retained for them, although the specific term 

 "spiralis" is hardly applicable to the fully developed 

 worm. 



In what way man becomes infected with the embryos of 

 this Trichina I shall not here describe in detail. That he 

 derives his Trichina, like the Echinococcus, from the Dog, 

 can scarcely be doubted. I will in addition merely remark 

 that I have, perhaps superfluously, instituted an experiment 

 in elucidation of this point, having administered to a young 

 pig the intestine of the last-mentioned dog, with its contents. 

 We know that the Trichina in the encysted condition also 

 occurs in the Pig ; the experiment consequently may be ex- 

 pected to prove successful. 



Under these circumstances I shall probably have an oppor- 

 tunity of communicating further observations on the 

 subject. 



A third dog, which was examined twelve days after feeding, 

 afforded only a few Trichinae, which differed in no respect from 

 the preceding. They were found exclusively in the colon — a 

 circumstance inducing the belief that the mature Trichina, 

 notwithstanding the abundance in which it is at first found, 

 nevertheless remains only a short time in its nest. And it 

 may also be stated, that in previous experiments, in animals 

 examined some weeks after feeding, no vestige of Trichina 

 was ever met with. 



The pigs referred to arc still alive, and have in the mean- 

 while served for experiments of another kind. Their faeces, 

 on the sixth day after the feeding, contained no Trichina. 



[The further results of Professor Leuckart's observations on 

 Trichina are communicated in the ' (Jottinger Nachrichten' 

 for April 30th, and may be thus briefly summed up.] 



That the Trichina spiralis, as met with in the muscular 

 tissue, represents the immature condition of a ncmatoid 



