_Natural prey._--_Arenivaga roseni_ and _Polyphaga saussurei_, Turkmen S.S.R. (Vlasov and Miram, 1937): These desert cockroaches are found in burrows of rodents and desert turtles around Ashkhabad. Reduviids are their main enemies. Vlasov (1933) found nymphs of _Reduvius christophi_ Jak. and _R. fedtschenkianus_ Osch. in similar burrows in this same area, although he did not specifically cite them as enemies of the desert cockroaches. Family NEPIDAE =Ranatra= sp. _Experimental prey._--Cockroaches, U.S.A. (Hoffman, 1924). Order NEUROPTERA Family ASCALAPHIDAE =Undetermined larva= _Experimental prey._--_Blattella germanica_, Kenya Colony (Someren, 1924). Order DIPTERA From the few observations that have come to our attention, it seems that flies are comparatively rare parasites in cockroaches. Family PHORIDAE =Megaselia= sp. _Host._--Eggs of _Parcoblatta_ sp., Ohio (Edmunds, 1952a). Family CONOPIDAE =Stylogaster stylata= (Fabricius) _Hosts._--Cockroaches, Brazil (Souza Lopes, 1937): L. Travassos was quoted as having observed this species pursue cockroaches that were escaping columns of the army ant _Eciton_ sp. Souza Lopes (1937) stated that the female deposits eggs on the cuticle of the host near the end of the body; the egg is barely inserted and two recurrent hooks prevent it from falling off. Souza Lopes (1937) also observed other species of _Stylogaster_ pursue Orthoptera, but he was unable to devote proper attention to the behavior of the flies. =Stylogaster= spp. _Hosts._--_Chorisoneura_ sp., Brazil (Souza Lopes, 1937): An adult specimen was found in a museum collection with an egg of _Stylogaster_ attached to the posterior end of its abdomen. Cockroaches, Panama (C.W. Rettenmeyer, personal communication, 1959): "Seven species were collected hovering over army ant swarms and a few flies were seen apparently attacking cockroaches that had been flushed by the ants." Family LARVAEVORIDAE =Calodexia= (?) =venteris= Curran _Hosts._--_Periplaneta americana_, Brazil (Souza Lopes, 1937): Obtained complete evolution of the parasite in this host. This may have been an experimental host. =Calodexia= spp. _Hosts._--Cockroaches, Panama (Rettenmeyer, personal communication, 1959): Swarms of army ants are accompanied by about 20 species of _Calodexia_. These flies larviposit on the cockroaches, crickets, and possibly other arthropods that are flushed from cover by the ants. Larvae were found in one(?) cockroach. Larvae from an adult of _Calodexia_ were introduced experimentally into a cockroach and successfully reared. =Undetermined tachinids= _Hosts._--_Eurycotis floridana_, from Florida (Roth, unpublished data, 1953): Three larvae (det. by W.W. Wirth) were found in a living adult male. _Panesthia australis_, from Australia (Roth, unpublished data, 1957): Reared from a wild-caught cockroach that was maintained in a laboratory colony.