THE ALIMENTARY TRACT 167 
Brooks emphasizes the importance of certain grasses and 
musty fodder, systematic writers detail among the princi- 
pal causes of gastritis spoiled food, and in zoological 
gardens specific disease like hog cholera and entero- 
hepatitis are relatively uncommon while non-specific 
gastroenteritis is the most frequent diagnosis in causes 
of death. 
The other factors to which enteritis is ascribed are 
animal and vegetable parasites and mechanically oper- 
ative foreign bodies, the last being unimportant. Just 
how important the first mentioned are is a matter of some 
question which must be subjected to considerable study 
before any solution can be expected. 
If for no other reason than that the gross and minute 
pathological anatomy of gastro-entero-colitis is the same 
through the mammals and birds (aside from a few 
specific lesions like enterohepatitis, typhoid fever, etc.), 
while the food and bacteria vary, it would seem probable 
that the ultimate cause is the same, a poison which can be 
formed alike in the carnivorous and herbivorous gut, and 
not dependent upon bacteria, but upon the chemistry of 
the food or of the intestinal mucosa. To put the matter 
more simply, the lesions being the same under nearly all 
conditions is not the cause the same, and is it not a 
poisonous product from food or the intestinal lining. It 
is profitable here only to mention the marked similarity 
of enteric lesions under the differing conditions and in 
different orders. We shall study chartwise, the various 
forms of inflammation from the cardia to the anus in 
terms of their anatomical diagnosis and most probable 
etiology in an attempt to throw light upon the matter, and 
later present the physiology. System requires, however, 
some attention first to anatomical order so that a brief 
review of the esophageal and pharyngeal conditions 
is indicated. 
