MAY FLIES AND MIDGES OF NEW YORK 279 



the femora somewhat darker; the fore tarsi of the male bare or 

 nearly so, fore metatarsus somewhat shorter than the tibia, the 

 hind tibiae and tarsi thickly haired; wings whitish, spotless, 

 Halteres white. The female has a light spot on each humerus, 

 and the posterior legs have fewer hairs. Length 1 to 1.5 mm. 

 Greenland. Lundbeck. 



15. Orthocladius fugax n. sp. 



Larva. In little rolls or tubes of debris upon the flat rock 

 bottom of Cascadilla creek (Ithaca N. Y.) little bluish green 

 larvae with dark brown heads were found. These larvae are 

 rather more robust than those of many Chironomids, the 

 middle body segments being fully as wide as they are long. The 

 total length of a full-grown larva is from 3 to 4 mm. Head dark 

 brown, short, with the suture separating the dorsal from the 

 lateral sclerites quite distinct, the dorsal sclerite being elongate- 

 ov^al, acute-angled at its caudal margin, with three setae upon 

 each lateral margin, the most posterior of these being cephalad 

 of the middle transverse line; opposite this last seta near the 

 suture but upon the lateral sclerite is another seta a little caudad 

 of this, also near the suture there is still another, and on each 

 side near the ventral surface, directly ventrad of the paired eye 

 spot, there is a pair. The pale brown antennae (pl.25, flg.Sa) are 

 short, only about one half as long as the mandibles. The latter 

 is stout, its apical half blackened, and with a stout seta on its 

 side. The labrum (fig.3) has a somewhat blunt apex with a 

 few small setae; the epipharynx has the usual pair of arms the 

 ends of which are not conspicuously darkened. The maxilla 

 (flg.2 mx) has a short palpus and a few papillae and a group of 

 mesad projecting filaments. The labium is brown, has a deep 

 margin of black, the middle tooth is rounded, the first lateral has 

 a more or less distinct notch on its lateral edge, the remaining 

 laterals have rounded tips (fig.2 1). Each anterior proleg is pro- 

 vided with perhaps about 50 long and rather coarse pectinate 

 setae (fig.5) and many shorter ones. The posterior legs are each 

 provided with a number of claws, those on the periphery as 

 shown on pl.25, fig.9, those in the middle of the foot as shown in 

 fig.8. The papillae upon which the caudal setae are placed are 

 short and pale in color. The anal blood gills are rather long and 

 prominent (pl.25, fig.6). The diameter of the anterior abdominal 

 segments is considerably greater than that of the posterior. 



Pupa. Dark fuscous green. Length 2.5 to 3 mm. Respiratory 

 organ slender, broadened toward the apex, its surface roughened 

 (pl.25, fig.4) ; its length a little greater than the setae at the 



