208 Journal New York Entomological Society, [Vol. xxiii, 



fringe is black and well developed, it extends from near the cephalic 

 margin of segment three to the caudal margin of segment eight ; 

 above the lateral fringe on each segment occur minute, brown, paired 

 spine-like processes; the gills are well-developed, their number and 

 distribution are shown diagrammatically in pi. i6, fig. ii. The weakly 

 chitinized portions of the entire larva are thickly set with minute 

 spines. 



Pupa. — Length 13-17 mm., breadth 4-4.5 mm. In life the color 

 of the thorax and appendages is brown, the abdomen is green and 

 the lateral fringe is deep black. The antennae extend back to about 

 the caudal margin of the eighth segment they bear groups of short 

 setae on the dorsal sides of the second segments ; each side of the 

 labrum bears a group of about six long hooked setae; a row of sharp, 

 curved, forward pointing spines borders the caudal margin of the 

 eye; the second and third pairs of legs have well developed swimming 

 hairs and, in advanced pupae, show the black spines of the adult con- 

 spicuously ; the lateral fringe is well developed, commencing on the 

 caudal margin of segment five and turning under the abdomen at the 

 caudal margin of segment eight; the gills are well developed; the 

 last segment bears a number of setae and two backward pointing 

 processes, pi. 16, fig. 17. 



The Larval Case. — The length and breadth vary according to the 

 material found in its environment. It is always bulky and is usually 

 of the cross-stick type common in the genus. It may be made of 

 bits of leaves or plant stems or, sometimes, of seeds. When seeds 

 are used it does not show the tendency to cross the material. The 

 cavity is cylindrical and is always lined from end to end with a 

 sheet of silk. 



The Pupal Case. — DiiTers from the larval case only in having the 

 mesh of silk across its ends as illustrated in pi. 16, fig. 12. 



Chilostigma difl&cilis Walk. 



Larval Habitat. — The larvae of this species have been found by 

 us in a very limited area of a stream in the McLean swamp. The 

 stream is a small one, hardly more than a foot in width and three or 

 four inches in depth. It rises in a sphagnum bog and penetrates a 

 dense thicket of alder for about a half mile, when it enters a larger 

 stream. Through the alder thicket the waters are in deep shade. 



