Natural host.Blatta orientalis, France (Mercier, 1908a): The organism parasitized the fat body of the cockroach. Mitoses, often abnormal, were induced in the fat cells. Infected cockroaches were easily recognizable by their distended abdomens. The fat body became chalky white and showed through the intersegmental membranes.

Porter (1930) reported finding an unidentified microsporidian in the fat bodies of Blattella germanica and Periplaneta americana collected in South Africa. It may or may not have been a species of Plistophora.

Class CILIATA

Order HOLOTRICHA

Family PARAMECIIDAE

Paramecium sp.

Natural associate.—Cockroaches, U.S.A., Maryland (Cleveland, 1927): Three of 30 cockroaches collected in the basement of a department store had paramecia in their stomachs but none in the rectum.

Experimental associate.Periplaneta americana, U.S.A. (Hegner, 1929): Paramecia fed to the cockroaches were recovered from the crop at intervals from one-half to six and one-half hours. In no case were the protozoa recovered from the stomach alive.

Cockroaches, U.S.A., Maryland (Cleveland, 1927). About 200 starved cockroaches were fed a culture of Paramecium. Few, if any, of the protozoa were killed in the stomach during the first two hours, but all were killed within 5 to 6 hours after ingestion.

Family ISOTRICHIDAE