Fresh-Water Entomostraca from China and Sumatra. 29 



antennæ well-developed, extending to the tip of the terminal 

 claws. Masticatory lobes and palp of 1st pair of maxillæ 

 narrow linear in form ; 2nd pair of maxillæ with a well- 

 developed vibrator}^ plate. Caudal rami exceedingly large 

 and powerful, dorsal edge divided into a limited number 

 of coarse serrations, apical claws very strong and coarsely 

 dentated along the concave edge, apical seta slender, that 

 of the dorsal edge very small. 



Remarks. — This new genus is chiefly characterised 

 by the very delicate structure of the valves, and by the 

 unusual development of the caudal rami. It contains at 

 yet only a single species, to be described below. 



7. Leptocypris papyracea, G. O. Sars, n. sp. 



(PI. Ill, figs. 4, 4 a— c). 

 Specific Characters. — Female. Shell very much 

 compressed, seen laterally, oblong in form, greatest height 

 scarcely attaining half the length and occurring about in 

 the middle, dorsal margin evenly arched, ventral distinctly 

 sinuated in front of the middle, anterior extremity bluntly 

 rounded, posterior somewhat narrover and transversely trunc- 

 ated ; — seen dorsally, narrow fusiform, greatest width scar- 

 cely exceeding ^ of the length, both extremities acuminate. 

 Valves perfectly equal very thin and pellucid, surface densely 

 striolate and provided at each extremity with scattered hairs ; 

 muscular impressions far in front of the middle. Eye some- 

 what remote from the dorsal face, pigment light yellowish. 

 Caudal rami equalling in length half the shell and highly 

 chitinized, almost straight, dorsal edge divided into 6 to 7 

 strong serrations, outer apical claw not attaining half the 



