Botulism stands almost alone among human diseases in that the microbic cause is not a tissue invader transmitted directly through the agency of man or the higher animals or by means of insects, but is primarily a saprophyte, owing its pathogenic power to a toxin produced in food substances outside of the animal body. From the standpoint of prevention, therefore, the real habitat and distribution of Bacillus botulinus become matters of fundamental significance. Certain forms of animal and plant life dangerous to man have a definite localization on the earth's surface. Poisonous snakes, the mosquito carrier of yellow fever virus, and poison ivy are all restricted to certain areas; is this true of B. botulinus?
The obscurity that still surrounds the natural living conditions of most of the spore-forming anaerobes has been especially marked in the case of B. botulinus. With the exception of an isolated finding in 1897 by