Further Observations on Plistophora kudoi, a Microsporidian of the Cockroach

In the mid-gut of Blatta orientalis Linnaeus, collected from time to time on the campus of the University of Illinois, Urbana, Illinois, in the summers of 1937-1940, the senior author occasionally noticed protozoan spores, apparently of a microsporidian. This parasite may be identical with one of undetermined nature observed by Perrin (1905), although the spores he saw, being about 1-2 p long by 0.5 [1 wide on permanent preparations, were somewhat smaller than those described below in the living condition.