In Siberia, Burr (1926, 1939) found _Blattella germanica_ and bedbugs inhabiting the same room. Mellanby (1939) studied the populations of an animal house in which bedbugs and cockroaches occurred in large numbers; the bugs apparently were not attacked and their numbers increased greatly over a period of a few weeks (Johnson and Mellanby, 1939). Wille (1920) placed starved _B. germanica_ with bedbugs for 20 days, but the cockroaches failed to attack the bugs. In India, captive adults and nymphs of two species of house cockroaches would not touch living bedbugs or their eggs (Cornwall, 1916). In laboratory experiments Gulati (1930) found that _Periplaneta americana_ ate young bedbugs which had soft, blood-filled abdomens; adult bedbugs with harder exoskeletons sometimes were rejected. The maximum number of bedbugs eaten by a cockroach was 3 out of 12 during a period of 48 hours. Johnson and Mellanby (1939), also in laboratory experiments, were unable to show that bedbugs can be controlled by _Blatta orientalis_ or that bedbugs are eaten to any extent by them. The existing evidence indicates that there is little basis for the often repeated statement that cockroaches destroy bedbugs in nature. As Lorando (1929) pointed out, assassin bugs, cockroaches, and red ants can hardly be considered as practical factors in bedbug control, though he did recommend the use of spiders. According to Martini (1952), cockroaches prey on mosquitoes and sand flies but we have been unable to find any original sources for these statements; the only reference we have found in which cockroaches and _Phlebotomus_ are mentioned together is a paper by Whittingham and Rook (1923); they fed ground-up cockroaches to larvae of _Phlebotomus papatasii_. Wharton (1951) reported that cockroaches and other predators attacked mosquitoes knocked down by insecticides and affected the number recovered. Cockroaches will on occasion attack and bite animals other than insects. In an earlier paper (1957a) we discussed about 20 reports of cockroaches biting man. The injury is usually confined to abrasion of the callused portions of hands and feet but may result in small wounds in the softer skin of the face and neck. We failed to include the following reference in the above-mentioned paper. Sonan (1924) had his toes and breast nibbled by cockroaches on Hiyakejima Island during sleep. He had previously learned from a policeman that _Periplaneta americana_ and _P. australasiae_ nibbled people on that island, but he had hardly believed it before he experienced the biting himself. INTRASPECIES PREDATION Those who have reared cockroaches in the laboratory have undoubtedly seen cannibalism occur in the cultures. Cannibalism has been observed among the common domiciliary species of cockroaches as well as laboratory colonies of _Leucophaea maderae_ (Scharrer, 1953), and _Blaberus craniifer_[12] (Saupe, 1928). Edmunds (1957)