Within the past two or three years the number of the animal parasites known or suspected to be the cause of disease has been notably increased, and if the extension of our knowledge in this direction continues at the same rate, we may have to modify our terminology to some extent, and instead of the name "bacteriology" as a branch of medical science, use some more comprehensive term. One of the latest additions to the list is the Myxococcidium stegomyiœ, which Drs. Parker, Beyer and Pothier1 of the Public Health and Marine-Hospital Service find as a regular denizen of the yellow fever contaminated mosquito. It is true that not all the steps necessary to positively assure us of the etiologic importance of this organism in yellow fever have yet been taken, or at least, if taken, have not been published, but it has
1. Report of Working Party No. 1,