116 
PSYCHE 
[December 
SOME EXPEimiEXTS WITH HYBRIDS. 
BY CAROLINE GRAY SOULE, BROOKLINE, MA.SS. 
In 1906 I had many cocoon.s of larvae from Cynthia $ by Promethea cj'. In 
1907 the moths emerged, and were hardly ilistingnishable from pure cynthia, though 
careful examination showed a duskier tint on the wings and a tendency toward the 
breaking into oblong patches of the inner marginal line on the hind wings. This 
however does not mean as much as the color difference, for some cynthia have the 
line more or less broken. The moths were as disappointing as the larvae had been, 
in following the cynthia marks so closely, and confirmed my belief that cynthia is 
prepotent in cross with any other species, though 1 have not been able to get moths 
from any other cross. 
On May .30th, two pairs of the hybrid moths mated, the eggs hatched on .lime 
19th, and the larvae lived through the third moult, dying, apparently from mere lack 
of vigor or “vitality.” 
On -lime 7th, two pairs mated, the eggs hatched on June 24th, and the larvae 
died in moulting for the third time. 
On June 10th, two pairs were mated all night and until dark June 11th, but no 
eggs were laid. They remated on June 12th, no eggs being laid till June loth. 
These hatched, the weather being very hot, on June 24th. The larvae died in 
moulting for the third time. 
June 19th, one pair mated, but no eggs were laid. 
The larvae were typical cynthia in looks, and very delicate. I had no ailanthus 
for them, but they ate wild cherry voraciously, preferring it to lilac or ash. Some- 
thing was amiss with the cherry, in Tyson, Vt., this year, and I found several larvae 
of -promethea, polyphemus and e.rcaecatvn, hanging from twigs lim]3 and lifeless, just 
as my hybrids hung in my tins. Indeed I have never before found as many dead 
larvae as this year, and nearly all on wild cherry. 
On IMay 19th, $ polyphemus mated with c? promethea for several hours, and 
laid many eggs which did not hatch. 
IMay 22d, $ promethea mated with a c? hybrid {cynthia 9 and promethea c?) 
but laid no eggs. 
IMay 2.3rd, 9 hybrid mated with c? promethea, but laid no eggs. 
May 27th, 9 cynthia and (J- cecrojiia mated, eggs were laid, and they remated 
on the 2Sth, more eggs were laid, but all were infertile. 
