The day before the parasite leaves the host, the cockroach shows an abrupt uneasiness and runs about, finally falling over on its back. The parasite larva emerges from the host through an opening it makes in the membrane between penultimate and last tergite. The host dies a few hours after the larva has left. The larva seeks a sheltered area and pupates within 48 hours. Adults emerge in 9 days (females) and 13 days (males) (Barbier, 1947). _Distribution._--Adult males have been collected in light traps in Hawaii (Van Zwaluenburg, 1946), and the first female was reported by Weber (1948); the parasite is now established in the islands around Pearl Harbor (Dr. F. X. Williams, personal communication, 1953). The U. S. National Museum has specimens of _R. pectinicornis_ from England, Guatemala, Hawaii, Panama, and from Florida and Georgia in the U. S. (Dr. E. A. Chapin, personal communication, 1953). Kono (_in_ Asano, 1937) reported two species in Japan. It is noteworthy that all these records are from localities adjacent to oceans and on ships; none are from interiors of continents. The only biological data were obtained from parasites found on board ships. Sundevall (1831) believed that the parasites boarded his ship with their hosts during loading in Calcutta, since before that not any were seen on board. Barbier (1947) suggested that the parasite must be spread very easily in ports between neighboring ships by parasitized cockroaches in baskets or sacks of provisions. =Ripidius scutellaris= Heller _Natural hosts._--Blattidae, Philippine Islands (Schultze, 1925). Family DERMESTIDAE =Dermestes ater= De Geer _Common name._--Black larder beetle. _Natural prey._--_Blatta orientalis_, U.S.A. (Roth and Willis, unpublished data, 1953): _Dermestes ater_ is generally a scavenger, but we have seen adult beetles, which had developed in our cockroach colony, clinging to and feeding on living oriental cockroaches, eventually killing them; the beetles probably attack only the weakened or injured cockroaches in a culture. This was a natural infestation of a laboratory culture by a predator. _Experimental prey._--_Blattella germanica_, oöthecae, U.S.A. (Roth and Willis, 1950): The beetle larvae can penetrate unhatched oöthecae of the German but not those of the American or oriental cockroaches. =Dermestes= sp. _Natural prey._--_Blatta orientalis_, oöthecae, U.S.A., Missouri: Rau (1924) stated that _Dermestes_ larvae often infest the egg cases of this cockroach; it is probable that Rau was referring to cockroaches in laboratory cultures. Order STREPSIPTERA