One has but to review the literature of dysentery to arrive at the conclusion that there is no fixed etiologic factor in this disease; that the lesions, which are mainly confined to the large intestine, are quite characteristic, but are induced by several different agents, is a pretty constant finding, and is worthy of consideration.
The Amœba coli is designated as the specific causative factor of dysentery, but here one is confronted with the fact that these bodies are found in less than one-half of the cases of all varieties and stages of the disease, and that the colon may be the normal habitat of amebæ, not only of this, but other amebæ—Amœba guttula, diaphana, vermicularis, oblonga, reticularis and proteus—which, it may be, are quite as culpable as Amœba coli. Moreover, these bodies are usually accompanied by other organisms, some pathogenic, and others which, by the proper environment,