143 



Remarks. This genus was proposed in the year 1900 by Kaufmann, and 

 as its type was considered Monoculus villosus of Jurine, which by most recent 

 authors had been referred to the genus Cypridopsis Brady. Kaufmann, how- 

 ever included in that genus 2 other species which evidently are not congeneric, 

 and which have been described above as members of the genus Pionoeypris. 

 The present genus is in particular distinguished by the very asymmetrical valves 

 and by the structure of the maxillae. From the genus Potatnocypris Brady it 

 differs essentially by the well developed natatory setae on the posterior antennae. 

 In addition to the typical species described below, Cypridopsis smaragdina 

 Vavra and Potatnocypris maculata Aim are apparently referable to the present 

 genus. 



62. Cypridopsella villosa, (Jurine). 



(PI. LXVI) 



Monoculus villosus, Jurine, Hist, des Monocles, p. 178, PI. XIX, figs. 14, 15. 

 Syn: Cypris Westwoodi, Baird. 

 . Cypridopsis villosa, Brady. 

 Potatnocypris villosa, Aim. 



Specific Characters. Female. Shell, seen laterally, triangular reniform 

 in shape, greatest height in the middle and about equaling 3 /5 of the length, 

 dorsal margin boldly arched in the middle and sloping rather steeply both in front 

 and behind, ventral margin deeply sinuated, anterior extremity obliquely rounded, 

 posterior rather narrower and somewhat deflexed, with the lower corner obtuse; 

 seen dorsally, narrow oblong or lancet-shaped, with the greatest width in 

 the middle and not nearly attaning half the length, both extremities pointed 

 and nearly equal. Surface of shell finely dotted and clothed with coarse recurved 

 hairs. Natatory setae on posterior antennae finely ciliated and extending some- 

 what beyond the tips of the apical claws. Maxillae with the distal joint of 

 the palp broader than long and armed with 4 spines, one of them forming 

 the immediate continuation of the joint; spines on outermost masticatory 

 lobe smooth. Vibratory plate of maxillipeds replaced by 2 small bristles. Caudal 

 rami with the flagellum very slender and about twice as long as the stem. 

 Genital lobes rather large, oblong in shape and somewhat widening in front, 

 hooked process strongly chitinised. 



Colour of shell light grass-green. 



Length of adult female 0.72 mm. 



Male unknown. 



Remarks. The identity of the above-described form with Jurine's Mono- 

 culus villosus seems to me to be indoubitable, and has also been admitted 



