STENHELIA. 33 



tlie first thoracic segment, and produced into a long 

 curved rostrum (fig. 1). Abdomen (fig. 1) 5-jointed, 

 the first two joints not coalescent. Anterior antenna 

 8-jointed, the second joint reaching to the extremity 

 of the rostrum ; the fourth joint is somewhat longer 

 than the preceding three, and the last four are much 

 shorter and more slender, their entire length being 

 only equal to that of the two preceding joints ; the 

 second, third, fourth, and eighth joints each bear several 

 apical setae, the other joints very few. Middle joint of 

 the inner branch of the posterior antenna (fig. 4) very 

 small. The second foot-jaw (fig. 8) has two spine-like 

 setae on the inner margin of the slender, oblong hand. 

 Outer margins of the swimming-feet densely fringed 

 with spine-like setae ; first joint of the inner branch of 

 the first pair elongated, nearly twice as long as the two 

 following joints ; second joint smaller than the third ; 

 the outer branch scarcely reaches beyond the apex of 

 the first joint of the inner branch; branches of the 

 second, third, and fourth pairs al!3-jointed and nearly 

 equal, joints long and slender (fig. 10). Fifth pair 

 well developed (fig. 12), basal joint broad and long, 

 fringed with small hairs and provided also with five 

 stout plumose setae on the apex and internal margin ; 

 second joint broadly ovate, bearing five marginal setae. 

 The third segment of the abdomen is the shortest, the 

 fourth the longest ; caudal segments about as long as 

 broad ; outer terminal setae very thick for the first 

 half, then suddenly tapering to a hair-like fineness 

 (fig. 14) ; inner setae about twice as long, stout and 

 shortly plumose. 



VOL. II. 



