116 



BULHETIN 15 8, UNITED STATES NATIONAL MUSEUM 



Upper, Middle, and Lower Cotiiit Ponds, Barnstable; Long Pond, 

 Barnstable; pond beside State road in East Falmouth; Crescent 

 Lake, Centerville, Barnstable; Ice Pond, Quisset, Falmouth; Flax 

 Pond, Falmouth; West End Pond, Naushon Island; Flax Pond be- 

 tween North and South Pocasset in Bourne; Red Brook Pond, 

 Bourne; found in small numbers in Clear Pond, Chatham; Great 

 Pond, Barnstable; French Watering Place, Naushon Island. 



Distribution. — Mountain lakes of Western United States (Marsh, 

 Herrick, Forbes). 



Color. — Transparent with a decided yellowish-brown tinge, deep- 

 est on the dorsal .surface; bases of the swimming legs and ventral 



Figure 77. — EpiscJiura nevadensis: a. Female, dorsal, showing peculiar 

 spermatopbore coiled around genital segment ; b, young female, fifth 

 legs ; c, adult male, fifth legs ; d, male, dorsal ; e, young male, fifth legs ; 

 f, adult female, fifth legs 



surface of the genital segment blue; eye dull red; metasome seg- 

 ments with a narrow blue band across their posterior margins; 

 ovaries and oviducts brown ; rami of swimming legs reddish ; caudal 

 setae bluish. 



Female. — Head separated from the first segment ; fourth and fifth 

 segments completely fused; genital segment a little wider than the 

 abdomen and protuberant on the ventral surface; caudal rami twice 

 as long as wide, each with three equal apical setae and a small spine 

 at the outer and inner corner, and a fringe of cilia along the inner 

 margin; spermatopbore elongate, cylindrical, and wrapped around 

 the genital segment like a bracelet ; segments of fifth legs increasing 

 in length distally, the end segment with three longer apical spines 

 and three shorter ones on the outer margin. Total length, 1.75-2 mm. 



