352 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I4I 



56 percent of oriental cockroach oothecae were parasitized during 

 these tests. 



Evania appendigaster was introduced from Hawaii into Canton 

 Island in 1940 against Periplaneta americana, and it has become 

 established (Dumbleton, 1957). This parasite was also successfully 

 introduced into Samoa (Dumbleton, 1957). 



Cockroach-hunting zvasps. — An earnest attempt has been made to 

 establish in Hawaii wasps that prey on cockroaches. Just how effec- 

 tive these wasps are in controlling cockroaches is still unknown. Doli- 

 churus stantoni was introduced from the Philippines in 191 7 and 

 spread to several of the Islands (Swezey, 1920, 192 1 ; Williams, 

 1944). Bridwell (1920) stated that as a result of this introduction 

 there was a great decrease in cockroaches of the genus "Phyllo- 

 droniia." A number of Podium haematogastrum from Brazil were 

 liberated in Honolulu (Williams, 1925) but did not become established 

 (Williams, 1928). The effectiveness of Podium was questioned by 

 Williams ( 1928) who observed that Podium "destroyed innumerable 

 Blattidae, which nonetheless swarmed in their neighborhood, and I 

 must confess from my observations on the various cockroach-hunting 

 wasps that the blattid more than holds its own alongside its enemy." 



Introductions of Ampulex have proved more successful. Ampulex 

 canaliculata was introduced into Hawaii from the United States (Wil- 

 liams, 1928a, 1929). Williams also introduced A. compressa into 

 Hawaii in 1940, and the species was reared in large numbers for 

 distribution (Pemberton, 1942). A. compressa has since become 

 established on most of the Islands (Pemberton, 1945a, 1947; Wil- 

 liams, 1946; Van Zwaluwenburg, 1950). The thousand of A. 

 compressa now found in the Hawaiian Islands are all descendants of 

 three wasps captured in Noumea, New Caledonia (Williams, 1944). 

 According to Williams ( 1941 ), the number of cockroaches was notice- 

 ably reduced at the University of Hawaii poultry farm, where some 

 A. compressa were released. Pemberton (1953) believed that this 

 wasp has become sufficiently abundant to be of definite value. Sim- 

 monds (1941) recommended importing A. compressa into Fiji for 

 cockroach control. A. compressa was introduced from Hawaii into 

 Guam in 1954 against Periplaneta americana and into the Cook Is- 

 lands in 1955 against Periplaneta spp. ; it is not yet known whether the 

 parasite became established in either place (Dumbleton, 1957). 



