_Natural host._--_Blatta orientalis_, Germany (Avrech, 1931): Found in cells lining the lumen of midgut and caeca. The whole upper part of the epithelium was filled with sporangia and spores. Class ASCOMYCETES Order ENDOMYCETALES Family SACCHAROMYCETACEAE =Saccharomyces cerevisiae= Hansen _Natural vector._--_Blaberus craniifer_, U.S.A. (Wedberg et al., 1949): In feces. =Saccharomyces= sp. _Natural vector._--_Blattella germanica_, U.S.A. (Janssen and Wedberg, 1952): Found consistently in alimentary tract of _B. germanica_ fed sucrose solutions. Order HYPOCREALES Family HYPOCREACEAE =Cordyceps amazonica= Hennings _Natural host._--Cockroaches, British Honduras (Mains, 1940). =Cordyceps blattae= Petch _Natural host._--_Blattella germanica_, Ceylon (Petch, 1924): Collected at Hakgala twice. A slight covering of brown mycelium overran the insect and fastened it to the underside of a living leaf. Order LABOULBENIALES Family LABOULBENIACEAE =Herpomyces amazonicus= Thaxter _Natural host._--_Nyctibora obscura_, Brazil, Natal (Thaxter, 1931): On antennae. =Herpomyces anaplectae= Thaxter _Natural hosts._--_Anaplecta_ sp., Venezuela, Caracas (Thaxter, 1905, 1908); Trinidad (Thaxter, 1931): On antennae. Cockroach, Sumatra (Thaxter, 1931). =Herpomyces appendiculatus= Thaxter _Natural host._--_Platyzosteria scabra_, Australia, N.S.W. (Thaxter, 1931): On antennae. =Herpomyces arietinus= Thaxter _Natural hosts._--_Ischnoptera_ sp., U.S.A., Georgia (Thaxter, 1908). _Parcoblatta uhleriana_, U.S.A., Massachusetts (Roth, unpublished data, 1957): The nymphs were in a culture of _Parcoblatta virginica_ which was infected with this fungus; it is possible that these _P. uhleriana_ became infected by contact with _P. virginica_. Fungus identified by Dr. R. K. Benjamin. _Parcoblatta virginica_, U.S.A., Massachusetts (Roth, unpublished data, 1957): Fungus determined by Dr. R. K. Benjamin. Fungus found on antennae, palpi, legs, body surface (pl. 27, A). _Parcoblatta_ sp., U.S.A., Kentucky, Massachusetts (Thaxter, 1902, 1908): On antennae. It is likely that Thaxter's host records (certainly those assigned to _Temnopteryx_ and possibly those assigned to _Ischnoptera_) were species of _Parcoblatta_. Hebard (1917) has shown that all the species referred to _Ischnoptera_ in the United States, except _I. deropeltiformis_, now belong in the genus _Parcoblatta_. All species originally referred to the genus _Temnopteryx_ in the United States are now synonymized with species of _Parcoblatta_. =Herpomyces chaetophilus= Thaxter _Natural hosts._--_Periplaneta americana_, Brazil (Thaxter, 1931). _Periplaneta_ sp., Zanzibar and Mauritius (Thaxter, 1902, 1908): On spines of legs, antennae, and cerci. =Herpomyces chilensis= Thaxter _Natural host._--Cockroach, Chile (Thaxter, 1918): On antennae. =Herpomyces diplopterae= Thaxter