Natural host.—Periplaneta americana, U.S.A. (Owen and Mobley, 1948): The digestive tract of this cockroach is the normal habitat of this yeast which was transmitted to sirup by the insects. The yeast superimposed a foreign taste, suggestive of malic acid, upon the original flavor of the sirup.
Torula gropengiesseri Lodder
Natural host.—Blatta orientalis, Germany (Gropengiesser, 1925; Lodder, 1934): Isolated from fat body and oöthecae. Gier (1947) is of the opinion that the so-called yeasts that supposedly may displace the bacteroids in the fat body (Mercier, 1907b; Gropengiesser, 1925) may actually represent poorly fixed and insufficiently stained bacteroids.
Torula rosea Preuss
Experimental host.—Blaberus craniifer, U.S.A. (Wedberg et al., 1949): Upon repeated feeding of massive doses of this yeast to the cockroach, these workers were able to isolate the organism from the feces up to six days thereafter. There was no evidence that T. rosea was pathogenic for B. craniifer.
Class PHYCOMYCETES
Order MUCORALES
Family MUCORACEAE
Mucor guilliermondii Nadson and Filippov
Natural host.—Periplaneta americana, U.S.S.R. (Nadson and Filippov, 1925; Filippov, 1926): Isolated and cultured from intestine.