226 Nerve-winged Insects; Scorpion-flies; Caddis-flies 
of moss or in a rotten log, in which they pupate, and from which the adult 
fly issues in about two weeks. 
The genus Corydalis (Fig. 311) is represented by a single species, C. cornuta , 
but it is such a conspicuous and wide-spread insect that it is probably the 
best-known species in the whole order 
Neuroptera. The adult fly is most com¬ 
monly called “hellgrammite,” while the 
larvae (Fig. 312), much used by fisher¬ 
men as bait, are known as dobsons or 
crawlers. But other names are often 
used. Howard lists the following array 
of names, collected by Professor W. W. 
Bailey, which are applied to the larva 
in Rhode Island alone: dobson, crawler, 
arnly, conniption-bug, clipper, water- 
grampus, gogglegoy, bogart, crock, hell- 
devil, flipflap, alligator, Ho Jack, snake- 
Fig. 312. 
Fig. 31 i. —Dobson-fly, Corydalis cornuta , male, with head of female above. (Natural 
size.) 
Fig. 312. —Larva of dobson'-fly, Corydalis cornuta. (Natural size.) 
doctor, dragon, and hell-diver. The insect is very common about Ithaca, 
N. Y., and Professor Comstock of Cornell University gives the following 
account of its life-history as observed by him there: “ The larvae live under 
stones in the beds of streams. They are most abundant where the water 
