OF WASHINGTON. 57 



Sepedon fuscipennis Loew. (Figs. 6 and 7.) 



These disgusting black maggots were not infrequent in the 

 collection of dead plants, scum and floating matter at the dam in 

 the cold lake and in the adjoining water. They rest and move 

 below the surface, parallel to it, suspended by the four radiate, 

 narrow plates with which the body terminates. These rest with 

 the upper surface dry, and expose the spiracles to the air. The 

 larval segments are distinctly ^-annulate, the color is blackish 

 with waved black lines showing by transparency. The puparium 

 floats in the water, resembling a seed. It is blackish above, 

 whitish on the sides, with a lateral reddish stripe containing seg- 

 mentary black dots ; below whitish gray, speckled with black 

 dots.* 



Chironomus anonymus Will. 



These larvas were first noticed in the blacksmith's rain-water 

 barrel. They are bright red in color, but usually remain in a 

 tube formed of granular sediment united together. The material 

 seems to be largely the excrement of mosquito larvae. They 

 wriggle with a slow squirming motion continuously, apparently 

 to aerate the tracheal filaments. The pupa also remains in the 

 case, but wriggles with a different motion as it has to aerate the 

 bunches of fine filaments on the prothorax. Shortly before the 

 emergence of the imago it rises to the surface. 



Larva (Fig. i). Head a little higher than wide, flattened, rounded, ob 

 lique ; clypeus large, triangular, high ; eyes in two small, angular patches ; 

 antennae moderate, simple; labium distinct with two simple hairs; a few 

 hairs on the surface of the head. Body slender, elongate, last two 

 thoracic joints gently enlarged, subconsolidated. On ventral side of pro- 

 thorax anteriorly a short bilobed process bearing a large tuft of slightly 

 curved spines ; between the yth and 8th abdominal segments ventrally a 

 group of long, thick, curving, subsegmented respiratory tubes ; a tuft of 

 four small processes on the last segment ; a group of hairs at the dorsal 

 tip ; anal tip conical, with a ring of curved spines.' Color bright coral red, 

 translucent; alimentary canal whitish, more opaque. 



Pupa (Fig. 2). Head nearly free ; thorax small, the wing cases partly 

 covering the long, coiled leg cases. A diffuse bunch of finely branching 

 respiratory filaments on prothorax. Abdomen long, tapering, gently 

 curved. 



Chironomus modes tus Say. 



These larvae occurred in cases similar to the preceding, but 

 they lived in the masses of Spirogyra and under the Lemna leaves 

 in the lake. They were much smaller and slenderer than the 

 other species and pale whitish in color. The larva is without the 



*This has just been figured by Needham & Betten, Bull. 47, N. Y. State 

 Mus., pi. 14, ff. 1-5, 1901. 



