16 — BULLETIN 1487, U. S. DEPARTMENT OF AGRICULTURE 
GELIS SPECIES 
The writers have found five species of (Pezomachus) Gelis parasitiz- 
ing Apanteles melanoscelus. They are Gelis bucculatricis (Ashmead) 
(figs. 3 and 4), which has been obtained in especially large numbers, 
G. urbanus (Brues), G. apantelis Cushman, G. nocuus Cushman, and 
G. wnutilis Cushman. The last three were found by Cushman to be 
new and have been described by him (5). Like many species of Hem- 
iteles, the various species of Gelis are not at all specific as regards 
host selection. In addition to attacking primary parasites of numer- 
ous different types, they sometimes become primary themselves, devel- 
oping within spider egg cocoons and in the cases or cocoons of certain 
Lepidoptera, like Coleophora and Bucculatrix. 
The species reared by the writers from A. melanoscelus have two or 
three generations annually, with no regularity in this respect, however, 
in any particular species; 
and in general habits and 
life history the five species 
are practically identical. 
All of them hibernate as 
mature larvae in the Apan- 
teles cocoons and emerge 
as adults during the month 
of May. They appear to 
mate more readily under 
laboratory conditions than 
re most ichneumonoids. 
* Whether fertilized or not, 
Lz the females oviposit freely 
pee & A, Rn : 
* i, Bence in cocoons exposed to them. 
& y The eges, scarcely distin- 
ay oe guishable from those of 
ae y) \rene 5 : . : 
= “Sex species of Hemiteles in size, 
shape, and general appear- 
ance, are deposited ex- 
ternally upon the Apan- 
teles larvae within the co- 
coons; and they hatch in 
about two days. The 
period of larval growth is 
very short, the host being completely consumed within four to six 
days after the hatching of the egg. In this short space of time the 
hyperparasitic larva passes through five stages. In the case of the 
summer generations only a few days are spent as quiescent mature 
larvae before pupation; and the pupal period averages 7 to 10 
days. The time consumed in developing from egg to adult is nor- 
mally about 18 days, with 14 days the minimum and 24 days the 
maximum observed. With the hibernating generation the fully de- 
veloped larvae remain in the host cocoons from August until the 
following spring. 
According to the writers’ observations, the males of apantelis, 
nocuus, and inutilis are always winged, whereas in urbanus and 
bucculatricis both winged and wingless males occur. In all five 
species males are always produced in parthenogenetic reproduction, 
Fig. 3.—Gelis bucculatricis, female 
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