294 NEW YORK STATE MUSEUM 



three dorsal stripes, the sternum and the metanotum brown, 

 the long hairs in the longitudinal rows and those on the scutel- 

 lum brown. Abdomen brown, with blackish hairs, posterior 

 margins of the segments cinereous white; the genitalia brown, 

 the lateral lobes long and stout. Legs yellowish or testaceous, 

 the tarsi a little darkened, fore legs with short, the middle and 

 hind legs with long hairs. Fore metatarsus about one fourth 

 longer than its tibia. Wings hyaline, appearing somewhat dusky 

 on account of the dark hairs which cover them; veins yellow, 

 margin deeply fringed, venation as figured. Halteres yellow, the 

 knob sometimes slightly infuscated. 



Female. Face, basal joints of the antennae and the hairs of 

 the thorax more yellowish ; otherwise like the male. Ithaca N. Y. 

 July. 



12. Tanytarsus muticus n. sp. 



(P1.30, fig.20) 



Male. Yellowish, with three reddish brown thoracic stripes. 

 Head yellowish or greenish, palpi and proboscis yellow; antennae 

 including the hairs and the basal joint brownish. Dorsum of 

 the thorax greenish yellow, with three broad reddish brown 

 stripes, metathorax and sternum brown; scutellum and pleura 

 yellowish. Abdomen greenish, yellow, somewhat infuscated. 

 Hairs pale; genitalia yellow in color and elongate. Legs yellow, 

 somewhat darkened, except the trochanters and bases of fen^ora; 

 the middle and hind pairs longer haired than the fore pair; fore 

 metatarsus one third or one fourth longer than its tibia. Wings 

 hyaline, hairy, veins pale yellow; venation as figured. Halteres' 

 yellow. Length 2.5 to 3 mm. Ithaca N. Y. 



13. Tanytarsus exiguus n. sp. 



Larval case. Numerous fibrous, slender, conical cases are found 

 attached to the rocks in the bottom of shallow brooks in places 

 where the water flows most swiftly during the summer months. 

 Hundreds of these cases may be sometimes found upon a single 

 piece of roek no larger than a man's hand. The cases are slender, 

 conical, with a basal stem and three, or occasionally four, apical 

 filaments; the body is about 3.5 to 4 mm. in length. The color is 

 a pale brown like that of dried grass ; the structure is fibrous like 

 that of a Simulium case. The case is reinforced longitudinally 

 by three ribs, the basal prolongations of the filaments; the stem is 

 slightly enlarged at the base, by which it is attached to the rocks. 

 During the early summer most of the cases will be found attached 

 by the stem alone, but later in the season most of them lie flat on 

 the rock and are attached along one side like Simulium pupal 

 cases, Within this case is a small greenish yellow larva, or later, 



