BIOTIC ASSOCIATIONS OF COCKROACHES — ROTH .^t WILLIS 255 



The extent of host selection varies among these parasites ; some 

 species will oviposit into the eggs of more than one species of cock- 

 roach, but others show some degree of host specificity. Positive selec- 

 tion of specific hosts by certain parasites appears in correlative data 

 from different investigators on pages 235 to 254. There is a small 

 body of data that shows nonacceptance of certain hosts by some of 

 these wasps. For example, Comperia merceti would not parasitize 

 eggs of Blatta orientalis or Periplaneta americana in the laboratory 

 (Lawson, 1954a). We (unpublished data, 1957) exposed a soft 

 ootheca, recently removed from Eurycotis fioridana, to C. merceti; no 

 wasps developed ; we had similar negative results with C. merceti and 

 oothecae of B. germanica. We (1954b) could not induce Tetrastichus 

 hagenozvii to parasitize eggs of Blattella germanica, B. vaga, or Parco- 

 hlatta virginica in the laboratory. In our experiments, T. hagenozvii 

 oviposited into eggs of Supella sup ellect ilium, but the wasp eggs either 

 failed to hatch, or if they hatched, the larvae died before completing 

 development. Neither would T. hagenozvii parasitize eggs of N. 

 rhomhifolia (Roth and Willis, unpublished data, 1957). Anastatus 

 tenuipes would not parasitize the eggs of Latihlattella lucifrons He- 

 bard, Periplaneta americana, B. germanica, or B. vaga (Flock, 1941). 

 Anastatus floridanus would not oviposit into eggs ol S. supellectilium 

 and only rarely into eggs of P. americana or B. orientalis (Roth and 

 Willis, 1954a) ; in the laboratory, this wasp could not be maintained 

 beyond one generation on the eggs of P. americana. Edmunds 

 (1953b) could not induce Prosevania punctata to parasitize eggs of B. 

 germanica. Cros (1942) induced P. /'Mwc/ato to oviposit into a mantid 

 ootheca, but neither mantids nor parasite developed. 



COCKROACH-HUNTING WASPS 



A number of wasps of the families Ampulicidae, Sphecidae, and a 

 very few species of Pompilidae have been found to provision their 

 nests with nymphal or adult cockroaches. This habit of preying on 

 cockroaches is primitive (Leclercq, 1954) ; Leclercq (personal com- 

 munication, 1955) stated that this habit is always associated with the 

 conservation of a number of structures considered as archaic from a 

 purely morphological point of view. 



The records of wasps of the genus Astata capturing cockroaches 

 (e.g., Sickmann, 1893 ; St. Fargeau in Sharp, 1899) "all trace back 

 to a questionable record by Lepeletier (1841) which probably was a 

 misidentification of the predator" (K. V. Krombein, personal com- 

 munication, 1956). Marshall (1866) suggested that the braconid 

 Paxylomma huccata Breb., which he found frequenting cockroach 



