THE IRlCniNA. 



I(i9 



by six tuberdes. Eustrongylus papillosus Diesing, accord- 

 iug to Wymiiu, lives coiled up in the brain of tlie anhiuga, 

 •or snake-bird of Florida. E. buteonis Packard was found 

 living under the eyes of Buteo Swainisoni, and E. chordeilis 

 Packard iu the brain of the night-hawk. Doclimius duoden- 

 alis Dubiui lives iu the small intestine of man. 



Trichocephalus diapar Rudolphi (Pig. 110) lives in the 

 coecum of man, with the smaller anterior part of the body 

 buried in the mucous membrane. 



The most formidable round worm is the Trichina spiralis 

 Owen (Fig. 117). The body is regularly 

 cylindrical, tapering gradually from the 

 posterior end to the liead. The end of the 

 body of the male is without a spiculum, but 

 with two conical terminal tubercles. It is 

 1.5 millimetres long. The female is 3 mil- 

 limetres in length. 



Viviparous females begin about eight days 

 after entering the intestine of their host to 

 give birth to the larvae, wliicli bore tlirough 

 the walls of the intestines of their host, 

 passing into the body-cavity, and partly in- 

 to the connective tissue, and also, by means 

 ot the circulation, into tlie muscles. In 

 about fourteen days the worm coils up 

 spirally iu a cyst (Fig. 117), which eventu- 

 ally becomes calcareous and whitish. AVlien encysted 'iii human 

 the flesh of the pig, infested by the encysted mfild.-Etef Scl- 

 larvaj, is eaten by man, the young worms *"^'' 

 are set free in the stomach of their new host, and in three 

 or four days become sexually mature. The female Trichina 

 IS capable of producing a thousand young. The original 

 host of the Trichina is the rat ; dead rats are often de- 

 voured by pigs, and the use of raw or jiartially cooked pork 

 as food is the means of infection in man. 



Another worm, occasionally parasitic in sailors and resi- 

 dents of the East Indies, is the Filaria medinensis Gmelin, 

 or Guinea-worm. It is remarkably long and slender, some- 

 times over two feet in length. Tlie female is viviparous, 



