AQUATIC INSECTS IX NEW YORK STATE 381 



Larva. Speciinous from W'ihmith and Axtou N. Y. [P1.37, 

 fig.l to (>]. I'ale brown with paler incisures; head brown, lab- 

 rum hairy, with serrated edge; fans with 50 to GO rays; man- 

 dibles with a pair of apical setae; hypopharynx as usual; labrum 

 [flg.G] with middle tooth rather prominent, its ventral surface 

 with five setae in each of the two rows; each of the three 

 branches of anal ])apillae with a number of lobes. 



Pupa. Six branched respiratory filaments; eight hooks curved 

 cephalad on dorsum of each of abdominal segments 3 and 4; 

 four hooks curved cephalad on ventral surface of each of seg- 

 ments 5, 6 and 7; a. close transverse row of small caudad pro- 

 jecting spines on dorsum of eighth segment, and a pair of short, 

 blunt tubercles on the anal segment. Cocoon of the wall pocket 



type. 



S. venustum, var. a 



Plate 37, fijj:.S-14 



A number of specimens bred from larvae and pupae taken 

 from Fall creek, Ithaca N. Y., differ in the adult stage from 

 V e n u s t u m as described above in being uniformly smaller 

 (length 1.5mm); having the base of wing brownish and not yel 

 low% and in having the last four abdominal segments of the 

 female a shining black instead of brown. The larva differs as 

 follows: in size averaging less than two thirds that of venus- 

 tum, labrum with its toothed edge w'ider in proportion to its 

 size than in v e n u s t u m , its teeth more nearly of a size, 

 the ventral setae three in each row plus a very small one. The 

 pupa differs in having 10 respiratory filaments in each tuft, 

 the hooks on segment 2 more distinct, and the tubercles on the 

 anal segments apparently wanting. 



S. piscicidium (Synonym of venustum) Riley 

 Am. Ent. 2:3G7 

 According to Coquillett this is a synonym of S. venustum; 

 but I -have larvae and pupae from Professor Needham, taken 

 at Saranac Inn N. Y., which, though agreeing with Riley's fig- 

 ures of piscicidium, differ decidedly from the larvae and 

 pupae of S. V e n u s t u m taken by Messrs MacGillivray and 

 Houghton at Axton N. Y. in 1901, and by Professor Comstock 

 at Wilmuth N. Y. Of ti;e adults of the Saranac Inn material 

 I have only alcoholic specimens, hence can not state definitely 

 wherein these differ from S. venustum from Axton N. Y. 

 excepting that it averages a little larger in size. For the pres- 

 ent I shall regard it as a variety, though in all the material 



