THE TRICHINA. 



169 



by six tubercles. Eustrongylus papiUosus Diesing, accord- 

 ing to Wyman, lives coiled up in the bruin of the anhiuga, 

 or snake-bird of Florida. E. bnteonis Packard, was found 

 living under the eyes of Birieo Swainsoni, and E. chordeilis 

 Packard in the brain of the night-haAvk. Doclimius duoden- 

 alis Dubini lives in the small intestine of man. 



Trichocephulus dispar Eudolphi (Fig. 110) lives in the 

 ccecum 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 head. 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 larvse, which bore through 

 the walls of the intestines of their host, 

 passing into the body-cavity, and partly in- 

 to the connective tissue, and also, by means 

 ol the circulation, into the muscles. In 

 about fourteen days the worm coils up 

 spirally in a cvst (Fig. 117), which evcntu- 



j v v o T?icr 11'"' 



ally becomes calcareous and whitish. When encysted in human 



i M i j? ji j? iij.1 i muscle. Greatly inai? 



the flesh of the pig, infested by the encysted mned.-- Alter Lt-uck- 

 larvtb, is eaten by man, the young worms art 

 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 partially 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. 



The female is viviparous, 



