BIOTIC ASSOCIATIONS OF COCKROACHES — ROTH & WILLIS 253 



entire lifespans; of the 125 oothecae, 32 were parasitized. The 

 average number of offspring per female was 66 (range 5-164) (Roth 

 and WilHs, 1954b). In Periplaneta americana: Each of 206 oothecae 

 was exposed to a single female wasp for 24 hours ; the average 

 number of offspring per female was 103 (range 50-139). Five 

 oothecae were left with each of 38 females for their entire lifespans ; 

 of the 190 oothecae, 81 were parasitized. The average number of off- 

 spring per female was 94 (range 45-168 [from original data]) (Roth 

 and Willis, 1954b). 



Number of parasites per ootheca. — In Eurycotis floridana: In the 

 laboratory, 3 oothecae that had been exposed to 20 female wasps 

 yielded an average of 648 parasites (range 606 [from original data] 

 to 685) (Roth and Willis, 1954b). In Neostylopyga rhomhifolia: 

 One ootheca yielded "jt, parasites (Pemberton, 1941). In Parcohlatta 

 sp. : Two oothecae yielded an average of 100 parasites (Edmunds, 

 1953a). In Periplaneta americana: 100 parasites per ootheca (Sein, 

 1923) ; 140 (Schmidt, 1937) ; 25 (Rau, 1940a) ; 7-38, average 33 

 (Usman, 1949) ; 71 (Wolcott, 1951) ; 4 oothecae exposed to 20 fe- 

 male wasps yielded an average of 204 wasps (range 164 [from 

 original data] to 261) (Roth and Willis, 1954b) ; average of 30-40 

 (Cameron, 1955) ; 39 oothecae yielded an average of 93 parasites 

 (range 12-187) (Edmunds, 1955). In Periplaneta australasiae : Oo- 

 thecae yielded an average of 40-50 adult parasites (Cameron, 1955) ; 

 about 50 (Shaw, 1925). 



Sex ratio. — 3 $$:i J* (Usman, 1949); 4 $$:i ^ (Cameron, 

 1955) ; 2-8 ??: I c^ (Roth and Wilhs, 1954b) ; 1.2 ??: i (^ (Ed- 

 munds, 1955). Parthenogenesis exists; the unfertilized eggs pro- 

 duced only males (Roth and WilHs, 1954b; Edmunds, 1955). 



Distribution. — Probably worldwide. Eastern and southern U.S.A. ; 

 Central and South America ; Europe ; Arabia ; Africa ; India ; For- 

 mosa ; Hawaii. 



Tetrastichus periplanetae Crawford 



Natural hosts. — Periplaneta americana, Mozambique (Crawford, 

 1910) ; Union of South Africa (parasites reared from oothecae 

 collected in Durban, Natal, by the City Health Department) : The 

 parasites were identified by Burks (personal communication, 1956). 

 Jamaica (Gowdey, 1925) ; Reunion Island (Bordage, 1913). 



"Domestic cockroach," Puerto Rico (Wolcott, 1951). 



