The use of specific egg parasites to control cockroaches has not been attempted extensively. Cros (1942) liberated a species of _Tetrastichus_ (=_Eulophus_ sp.; see p. 254) in his home in Algeria to control the oriental cockroach; as far as we know, he did not report the parasite's effectiveness in reducing the cockroach population. According to Zimmerman (1948) _Comperia merceti_, when accidentally imported, practically wiped out _Supella supellectilium_ in parts of Hawaii; he claimed to have controlled the brown-banded cockroach in a store building with this parasite. In some parts of Honolulu, almost 100 percent of the oöthecae of this cockroach were parasitized (Zimmerman, 1944). We (1954b) ran some simulated field tests in which we liberated _Tetrastichus hagenowii_ in rooms artificially seeded with oöthecae; from 28 to 83 percent of American cockroach oöthecae and 56 percent of oriental cockroach oöthecae 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 wasps._--An earnest attempt has been made to establish in Hawaii wasps that prey on cockroaches. Just how effective these wasps are in controlling cockroaches is still unknown. _Dolichurus stantoni_ was introduced from the Philippines in 1917 and spread to several of the Islands (Swezey, 1920, 1921; Williams, 1944). Bridwell (1920) stated that as a result of this introduction there was a great decrease in cockroaches of the genus "_Phyllodromia_." 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."