Wasps, Bees, and Ants 
479 
within the body. In the latter case the issuing winged adults have to bite 
their way out. The host usually dies before its time for pupation has arrived, 
but in some species it succeeds in pupating beforehand. The parasitic 
Hymenopterous larvae, while degenerate in the same way as the footless, 
Fig. 673. Fig. 674. 
Fig. 673.—A chalcid fly, Pteroptrix flavimedia. (After Howard; much enlarged.) 
Fig. 674.—A chalcid parasite, Aspidiotiphagus citrinus, of one of the scale-insects of 
the orange. (After Howard; much enlarged.) 
eyeless, antennaless maggots of house-flies, are not more so. Their parasitic 
habit has led to no such extraordinary structural specialization through 
degenerative loss or reduction of parts as is the usual condition in other 
parasites. 
While Lepidopterous larvae undoubtedly furnish the majority of hosts 
for the parasitic Hymenoptera, they are by no means the only ones. The 
eggs and pupae of Lepidoptera as well as the larvae, Diptera, Coleoptera, 
Hymenoptera in both egg and larval stages, some Hemiptera, especially 
Fig. 675.— Labeo longitarsis, a parasite which lives in a sac in the abdomen of a Fulgorid, 
Liburnia lentulenta. (After Swazey; five times natural size.) 
scale-insects (Coccidae) and plant-lice (Aphididae), the eggs of locusts and 
other Orthoptera, and some Neuroptera in egg and larval stage, may be 
infested; in fact the kinds of insects which may serve as hosts for the para¬ 
sitic Hymenoptera strongly outnumber the kinds that do not. 
While as a general rule each parasite confines its attacks to a single host- 
species, there are numerous exceptions; and on the other hand the host 
itself may be attacked by more than one parasitic species; most of our familiar 
Lepidoptera are parasitized by several different parasitic Hymenoptera. 
