THE VETERINARIAN AS A NATURALIST. 
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ra.dia.tiLS, ventricosus, and inflatus, in the stomach and intestines. 
The strongylus micrurus, in the trachea and bronchi. The eu- 
strongylus gigas, filaria lachrymalis and papillosa, common also 
to the horse. And, spiroptera scutata oesophagea bovis, found 
in the oesophagus. This has been given a new genus by Stiles 
of the Bureau of Animal Industry, viz.: Myzomimus, and the 
parasite, the myzomimus scutata. 
The sheep also harbois a number of round worms, the most 
common being the strongylus filaria, in the trachea, bronchial 
tubes, and parenchyma of the lung. The strongylus contortus, 
found in the abomasum. The strongylus filicollis and dochmius 
hypostomus, in the intestines. And, tricocephalus affinis, in the 
caecum, and sometimes in other portions of the intestines. 
The pig or hog, is the host of the following parasites of this 
class : The ascaris lumbricoides, sometimes named the ascaris 
suilla, found in the intestines. The tricocephalus cren- 
atus, also in the intestines. The spiroptera strongylina, in 
the walls of the stomach. The stephanurus dentatus, in the 
adipose tissue round the kidney. The sclerostomum dentatum 
and the echinorhyncus gigas, in the small intestines. The 
strongylus paradoxus, in the lungs. And, the trichina spiralis, 
imbedded in the muscles. This nematode, although one of the 
smallest of the intestinal parasites, requires more than merely a 
passing notice, as it is responsible for the disease in the human 
being known as trichinosis, trichiniasis, or “ flesh-worm-disease.” 
it exists in two distinct forms, viz.: the partially developed or 
encysted, and the fully developed or intestinal. The following 
is a short history of the trichina : In a partially developed state 
it is found encysted in the muscles of the hog. Here it is sexually 
immature, but when the human subject partakes of the flesh 
imperfectly cooked, in the stomach the cyst wall is ruptured, 
the embryo escapes, and in 48 hours it becomes sexually ma¬ 
ture. Coition takes place, aud in about 8 days after enter¬ 
ing the stomach, young are born viviparously, they commence 
to migrate, entering the muscular tissues of the abdomen chiefly, 
and there become encysted. During migration they cause an 
