248 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I4I 



Pteromaliis (apparently identified by Westwood) obtained from one 

 cockroach ootheca. This same record of Sells was published posthu- 

 mously in 1842, although in this paper he identified the host ootheca as 

 "Blaherus" maderae. Cameron (1955) lists a European record of 

 Pteromalus sp. from Periplaneta americana citing Girault (1914) as 

 the source of the record. Girault's record was apparently taken from 

 Westwood's footnote mentioned above.] 



Systellogaster ovivora Gahan 



Natural hosts. — Blatta orientalis, U.S.A., Illinois (Gahan, 1917). 



Parcohlatta pensylvanica, Canada, Ontario (Judd, 1955). 



Parcohlatta sp., U.S.A., Ohio (Edmunds, igS^a., 1953a). 



"Blattid," U.S.A., Maryland (Gahan, 1917). 



One ootheca of P. pensylvanica yielded 14 parasites with a sex ratio 

 of 2.5 55: I (^ (Judd, 1955). The average number of parasites in 

 II oothecae of Parcohlatta sp. collected in 1950-51 was 27 wasps (Ed- 

 munds, 1952a, 1953a). The adults made two to three emergence holes 

 in the ootheca (Edmunds, 1953a; Judd, 1955). 



Family EULOPHIDAE 



Melittobia chalybii Ashmead 



Natural host. — Periplaneta americana, U.S.A., Missouri (Rau, 

 1940a) : M. chalybii is normally a parasite of Coleoptera and 

 Hymenoptera (Peck, 1951). This is the only record from cockroach 

 eggs. Burks (personal communication, 1956) stated that this species 

 will attack any insect to which it is exposed and can be a serious pest in 

 insect cultures of practically any insect order. In nature it seems to 

 prefer the nests of aculeate Hymenoptera ; Rau suggested that the 

 parasites were probably brought into his laboratory with mud nests 

 of Sceliphron caementarium (Drury). 



Mestocharomyia oophaga Dodd 



Natural host. — Ellipsidion aiistrale, Australia, Queensland (Dodd, 

 1917). 



Syntomosphyrum blattae Burks 



Natural hosts. — Parcohlatta sp., U.S.A., Ohio (Burks, 1952; Ed- 

 munds, 1952a, 1953a) : Ten oothecae yielded an average of 92 wasps 

 (Edmunds, 1952a). Five oothecae, collected a year later, yielded an 

 average of 74 wasps ; adults sometimes made two to three exit holes 

 in the ootheca (Edmunds, 1953a). 



Cockroach, U.S.A., West Virginia (Burks, 1952). 



