Habitat.—Surface of the nematodes Hammerschmidtiella diesingi and Leidynema appendiculata in Periplaneta americana, U.S.A. (Hoffman, 1952, 1953): Eighteen percent of 192 nematodes found in 52 adult cockroaches were infected with the bacterium.

Order CARYOPHANALES

Family ARTHROMITACEAE

Arthromitus intestinalis (Valentin) Peshkoff

Synonymy.Hygrocrocis intestinalis.

Habitat.Blatta orientalis, Europe (Valentin, 1836; Robin, 1847, 1853; Peshkoff, 1940): Isolated from intestinal tract. The organism appears as fragments in fecal masses or as fibers adhering to the mucous membrane of the large intestine (Robin, 1853).

Cockroach, France? (Chatton and Pérard, 1913).

Order SPIROCHAETALES

Family SPIROCHAETACEAE