446 NEW YORK STATE MUSEUM 



it was an easy matter to determine the length of the egg period. 

 By visiting the region daily till the hatching took place, the 

 period Avas found to be nine or ten days. Hatching seems to 

 take place only in the dark. In the region of Ithaca in 1899, the 

 hatching took place mostly during the first half of June. It was 

 observed that many masses of eggs never hatch. Some masses 

 of old eggs, apparently dried and dead, were found to hatch 

 when placed in a moist bottle in the collector's pocket. In sev- 

 eral cases these were found to hatch within an hour from the 

 time they were taken. The only explanation is that they had be- 

 come too dry, and the moisture in the bottle helped to soften the 

 eggshells so that the young larvae could break through. 



Larva. The young larvae when hatched differ somewhat in 

 '..ppearance and structure from the older larvae above described, 

 specially in having relatively longer filaments and legs, and 

 larger heads with larger mouth parts and only two jointed 

 antennae. 



Miall [1895], who has made a study of S. 1 u t a r i u s , states 

 that the larvae live about a year in streams with muddy bot- 

 toms. My observation of S. infumata indicates that the 

 larval life is at least two years. However, the exact length is 

 yet to be determined more certainly. Miall states that he found 

 freshly hatched larvae of his species " wriggling out on leaves 

 many yards from the nearest stream or pond." I have seen 

 nothing like this, as S. infumata always places the eggs 

 where the young when hatched will fall directly into the water. 



The larvae live in the bottoms of streams which are either 

 muddy or sandy. I have most often found them in deep sand 

 or gravel, perhaps 6 inches or a foot below the bed of the stream. 

 At this depth the larvae of Corydalis, perhaps their worst ene- 

 mies, seldom find them. Tests made as to their food habits 

 show that they are carnivorous, and will eat soft bodied caddis 

 worms, ismall Ohauliodes larvae and even eat one another very 

 readily. The larvae do not come to the surface nor abandon 

 their aquatic life till nearly ready to pupate. When captured, 

 they often eject a black liquid from the mouth. This means of 

 •defense is much more commonly used by them than by the larvae 

 of Ohauliodes and Corydalis. 



Pupa. The pupae of this species have only once been found in 

 their natural conditions by the writer. Prof. J. H. Comstock 

 first found them buried several inches in the earth some yards 



