Distribution of Progeny by Cryptus inornatus Pratt (Hymenoptera: Ichneumonidae)

Extract

In a previous paper (Ullyett, 1949). the present writer outlined a tentative classification of insects serving as hosts to entomophagous parasites. This scheme was based upon the more obvious relationships that exist between parasite and host insect and those which might conceivably have some hearing upon the degree of efficiency with which the females of the former distribute their progeny among available hosts. Five main groups were recognized which reflected the differences occurring between the various kinds of hosts and parasites encountered in the field. Of these, examples have already been dealt with from two of the groups, viz., Group II, in which the host is normally active but is paralysed by the parasite before oviposition, as exemplified by the distribution of eggs by the Braconid, Microbracon hebetor Say among the larvae of Ephestia kuehniella Zell. (Ullyett. 1945); Group IIIA, in which the host is stationary and fully exposed as illustrated by the relationship between the eggs of Ephestia and the attack of Chelonus texanus Cress. (Ullyett, 1949).