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SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I4I 



1908). Most Species are hyaline, small and inconspicuous (Thaxter, 

 1931) and are usually, but not exclusively, found on the insects' 

 antennae. Species of Herpomyces are highly, but not completely, host 

 specific (Richards and Smith, 1954). While attached to the host, 

 these fungi appear like minute dark-colored, yellow, or white (e.g., 

 H. arietinus) bristles or bushy hairs (pi. 27, A). 



Richards and Smith (1955, 1955a) have studied the life history of 

 Herpomyces stylopygae on the oriental cockroach. The plants grow 

 only on living cockroaches, and the infection is disseminated by con- 

 tact. The mature plants are found mostly on the antennae (pi. 27, B), 

 either on setae or on hard or soft cuticle. Spores are ejected from 

 perithecia singly or in groups of 2 to 4 spores, although groups as 

 large as 12 spores have been found. The presence of single, paired. 



Herpomyces 

 stylopygae 

 Speg. 



Fig. I. — Diagram illustrating the relationship between a mature plant of 

 Herpomyces stylopygae and the integument of Blatta orientalis. (Reproduced 

 from Richards and Smith [1956], through the courtesy of Dr. A. G. Richards.) 



or multiple spore groups on the surface of the host was correlated 

 with the presence of single, paired, or multiple plants on infected 

 cockroaches. Development from spore to mature perithecia takes 

 about two weeks. The plant obtains nutriment from the host by 

 means of a tubular haustorium that extends through the cockroach's 

 cuticle and expands into a large bulb in the underlying epidermal 

 cells (fig. i). Infections on nymphs are lost when the nymph moults, 

 but infections on adults persist throughout life. However, nymphs 

 which have lost the fungus upon moulting are readily reinfected. 



