120 
Psyche 
[June 
young produced by old females near the end of their egglay- 
ing periods were all males, the sperms from mating having 
presumably been exhausted or were dead. Nothing in all 
this work suggested the possibility of thelytoky. The only 
other species of Sclerodermus bred in large numbers is S. 
macrogaster Ashmead which I found at Kingsville, Texas 
in January, 1920 and bred through several generations at 
Brownsville and at Washington until opportunity presented 
itself to put it in the hands of Dr. Wheeler for study. Since 
its biology differed but little from that of immigrans and 
its Hawaiian congeners, no detailed account of these studies 
was published. A note upon it was presented to the Ento- 
mological Society of Washington as recorded in 1922, 
(Journ. Washington Acad. Sci. 12:274). In this species also 
the phenomena of arrhenotoky were observed, probably in 
more instances than in immigrans. In it, as in immigrans, 
about one third of the females were winged while only a 
small fraction of one per cent of the males were wingless. 
If we review the conditions under which the progeny of 
Sclerodermus are produced we may see how a misunder- 
standing might arise. After the prey is mastered several 
eggs are laid upon it and the resulting larvae and their 
mother feed upon it. When the larvae are ready for trans- 
formation they spin separate coccoons so massed and 
attached to each other as to make it impossible to separate 
them without injury. The males emerge before the females 
and bite their way into the female coccoons and mate there 
before any of them have made their appearance in the 
open. The males are short lived and often only one or two 
appears in a mass of coccoons such as would produce eight 
females. Dr. Keeler intended keeping eight of the females 
of his F 3 generation virgin and from these supposedly 
virgin females only female progeny were produced. Since 
he does not detail the precautions taken to keep them from 
mating, I believe that these had mated before they were 
separated and that the few (normally not more than one 
fifth) male larvae died before transforming. 
