_Natural hosts._--_Blatta lateralis_, wingless females, Iraq (Hingston, 1925): Nesting sites are holes in palm trees, galleries of beetles, or tunnels in ground. The wasp first seizes a cockroach by the edge of its thorax and stings it in the thoracic region, then seizes the cockroach by an antenna and pulls and leads it to the nest. The wasp deposits her egg on the outer surface of the femur of the cockroach's midleg. The nest is closed with debris; later the cockroach recovers from the sting. The wasp larva first feeds externally, then bores into the cockroach and devours the internal organs. Pupation occurs inside the exoskeleton of the cockroach. =Ampulex canaliculata= (Say) _Synonymy._--_Rhinopsis caniculatus._ _Natural hosts._--_Ischnoptera_ sp., U.S.A. (Krombein, 1951). _Lobopterella dimidiatipes_, Hawaii (Williams, 1928a, 1929). _Parcoblatta pensylvanica_? MacNay (1954) referred to a rare sphecoid wasp in eastern Canada which provisioned its nest with nymphs and adults of _P. pensylvanica_. Dr. W. R. M. Mason (personal communication, 1957) wrote us that although this wasp was _Ampulex canaliculata_, it was not reared from the cockroach but was swept from a pine tree. There are no positive records linking _A. canaliculata_ with _P. pensylvanica_. _Experimental host._--_Parcoblatta virginica_, females, U.S.A., Missouri (Williams, 1928a, 1929): figure 6. Nesting sites are in twigs (Krombein, 1951). The adult behavior is similar to that of _A. compressa_; the female wasp imbibes blood that oozes from the amputated antennae of the cockroach; the egg hatches in 2-3 days, and the development of one male was completed in 33 days (Williams, 1929). [Illustration: FIG. 6. _Ampulex canaliculata_ attacking _Parcoblatta virginica_. A, Female wasp stinging her prey, c. × 4.8. B, Wasp's egg attached to the coxa of the mesothoracic leg of the cockroach. C, Larva of _A. canaliculata_ (about three-quarters grown) feeding on the internal organs of the host from the exterior, c. × 4. (Reproduced from F. X. Williams [1929], through the courtesy of Dr. F. X. Williams and F. A. Bianchi, Hawaiian Sugar Planters' Association.)] _Distribution._--U.S.A.: Connecticut south to Georgia; Ohio, Wisconsin, Missouri, Kansas; in open woods (Krombein, 1951). =Ampulex compressa= (Fabricius) (Pl. 35) _Synonymy._--Guĕpe ichneumon of Réaumur [Williams, 1929]; _Chlorion_ (_Ampulex_) _compressum_. _Natural hosts._--_Periplaneta americana_, New Caledonia (Lucas, 1879); India (Dutt, 1912); Reunion (Bordage, 1912). _Periplaneta australasiae_, Hawaii (Swezey, 1944). _Periplaneta_ sp., India (Maxwell-Lefroy, 1909). Cockroach. Mauritius (Réaumur, 1742); Burma (Bingham, 1897). _Experimental hosts._--_Neostylopyga rhombifolia_, _Periplaneta americana_, and _Periplaneta australasiae_, Hawaii (Williams, 1942, 1942a). Zimmerman's (1948) listings probably were taken from Williams.