AQUATIC INSECTS IN THE ADIRONDACKS 567 



metathorax and the first seven segments of the abdomen. Two stalks 

 occur together on each side of the segment, and these are in turn divided 

 into six or nine filaments. Instead of four stalks the mesothorax has two, 

 the metathorax three and the seventh abdominal segment one. Two 

 brown spots are very prominent on the ventral side of the eighth and of 

 the ninth segments. The anal hooks are on very large prolegs of one 

 joint each. A bunch of hairs is at the base of each hook. One or two 

 stout hairs arise near the base of the hook and extend to meet its point. 

 Pupa. Length 11 mm. Width 2 mm. Head pinkish. Thorax 

 white. Spurs on the tibiae arranged in the order 1-4-4. Abdomen 

 white with brick red on the dorsal side. Hooks pointing backward are 

 on the third, fourth, fifth, sixth, seventh and eighth segments. Plates 

 with spurs pointing forward are on the third and fourth segments. I was 

 able to make out but eight abdominal segments in this pupa. 



I Halesus species ? 



Plate 32, figures 3, 6; plate 33, figure 3 



Habitat. Larvae and pupae were found in Little Clear creek and 

 along the shore of Little Clear lake, specially on wood strewn bottoms. 



Occurrence. Larvae were quite plentiful during the entire period. 

 Pupae were obtained only at the last. Only two or three adults were 

 seen and those during the last week of work. A single specimen of this 

 species was bred Aug. 31, 1900. 



Case. (PI. ss, fig. 3) Case of thin pieces of wood placed at right 

 angles to the length of the case with their ends crossed. The coarseness 

 of the material used varies but is uniform 

 for each case. Length 18 to 20 mm. 

 Width 7 mm. 



Larva. (PI. 32, fig. 3) Length 15 mm. 

 Width 4 Dr c; mm. Head brownish black 

 with broad white stripes running obliquely 

 from the corners of the mouth along both 

 dorsal and ventral sides of the eyes. There 

 is a white spot where the inner pair of stripes 



. Fig. 37 Dorsal view of end of abdo- 



would unite if continued. The anterior half "^en of larva 

 of the dorsal side of the prothorax is black, the posterior half white. 

 The mesothoracic shield blackish brown bordered with black. Meta- 

 thorax yellow with large brown spots. Legs yellow with triangular white 

 spot on the outside of each femur at its joint with the tibia. Two spurs 

 on each tibia. Abdomen purplish, whiter beneath. Anal hooks are on 



