AQUATIC INSECTS IN NEW YORK STATE 471 
of the fore wings. Prothorax quadrangular, much narrower 
than the head and shorter than the mesothorax and the meta- 
thorax combined; large toothlike angles on the back part of the 
sides of the head; three large approximate ocelli facing at about 
120° from each other; antennae filiform moniliform or slightly 
serrate in a few species, as long as, or much longer than the 
head and thorax combined; mandibles prominent, not concealed 
by the labrum when closed, those of the male more or less elon- 
gated and annular, incurved, suited only for clasping. Wings 
numerously veined, the accessory veins of the radial sector ex- 
tending backward from R, in both pairs of wings, and media 
has more than two branches [fig. 26]; hind wings broad at base 
and folded in the anal area when at rest; wing expanse 100 to 
ASSN GL LMA ages 
CaN. 
Fig. 26 Fore wing of Corydalis cornuta x2 
150mm. Tarsi cylindric; male caudal appendages long and 
usually strongly forcipate; in the female they are short and 
simple. } 
Larva. When full grown, the larva is about 80 to 90 mm long. 
The general color is dusky; the head and thorax are supplied 
above with pretty figured markings; the whole body is supplied 
with black clavate projections except in the intersegmental folds 
and on the parts heavily clothed with chitin. The last four or 
five segments of the abdomen taper toward the caudal end of 
the body. The first eight segments of the abdomen are each pro- 
vided with a pair of unjointed lateral filaments, 6 to 7 mm long, 
somewhat clothed with hairs; the first seven of these segments 
are each provided with a pair of ventral tufts of tracheal gills. 
Spiracles are found on each of the first eight abdominal seg- 
ments and on the fold between the prothorax and the meso- 
thorax, and a rudimentary pair on a fold between the meso- 
thorax and the metathorax. On the last abdominal segment are 
