Experimental vectors.Blatta orientalis, Italy (Cao, 1898, 1906).

"Bacillus subtilis group"

Natural infection.Blatta orientalis, Italy (Ronzoni, 1949): Isolated from oöthecae.

† Bacillus tritus Batchelor

Habitat.—Isolated from feces (man?).

Natural vectors.Blatta orientalis, Poland (Nicewicz et al., 1946): Isolated from intestinal tract.

* Clostridium feseri Trevisan

Experimental vectors.Blatta orientalis, Italy (Cao, 1898).

Clostridium lentoputrescens Hartsell and Rettger

Habitat.—Soil, intestinal tract of man.