90 INSECUTOR INSCITI^ MlgNSTRUUS 



pale narrow curved scales over the shoulders; posterior ab- 

 dominal segments with white scales at both base and tip and a 

 few scattered in the black area ; wings brindled black and white, 

 white scales on all the veins, about half as numerous as the 

 black ones ; femora with more white scales than black ones ; 

 tibiae with the scales about evenly divided ; tarsi with the rings 

 broad, the last hind tarsal joint half white. 



The larva has the head with the upper tuft in threes or fours, 

 lower single ; pecten of the air-tube with long, well separated 

 teeth, but perfectly even, followed by a 6-haired tuft, the tube 

 over four times as long as wide, regularly tapered and a little 

 curved. Comb a moderate patch of about 14 scales, the scale 

 evenly fringed with spinules, the central spinule longest ; lateral 

 abdominal hairs double. 



Egg: Fusiform, one side flattened; central third nearly cylin- 

 drical, antemicropylar end slenderly tapered, the other more 

 abruptly conical with a mucilaginous cushion ; black, smooth, 

 laid singly. 



Type, Cat. No. 20351, U. S. Nat. Mus. 



Breeding in temporary open grassy pools, Little Yosemite 

 Valley, larvae and pupae, May 18, 1916 ; marshes at north end 

 of Fallen Leaf Lake and between Tallac and El Tahoe at the 

 south end of Lake Tahoe, June 1-2, 1916. 



The abdominal scales are mixed with brown. In a captured 

 female the pale scales are very extensive, on the apices as well 

 as the bases of the segments, and forming a diffused white 

 dorsal band the whole length. In a bred female the pale scales 

 are reduced, the basal white bands narrow and broken at the 

 sides, separated from the lateral spots. No apical pale scales 

 in this specimen except on the last two segments. Various 

 intergrades occur. 



This is a very distinct species of the cantans group, recog- 

 nizable by the large number of white scales on the wing veins, 

 some scales being present on every vein. Specimens with the 

 white dorsal band well developed on the abdomen present a 

 very unique appearance. 



