_172_ 



bear a very close affinity, so as to form with it a quite natural group. All the 9 

 species of Cythere recorded by G. W. Milller from the Gulf of Naples are 

 unquestionably referable to the present genus. In the following pages will be 

 described 5 species occurring off the Norwegian coast. 



76. Leptocythere pellucida, (Baird). 



(PI. LXXIX, fig. 1). 



Cythere pellucida, Baird, British Entomostraca, p. 173, PI. XXI, fig. 7. 

 Syn : Cythere confusa, Brady & Norman. 



Specific Characters. Female. Shell, seen laterally, elongate subqua- 

 drangular in shape, almost equally high throughout, greatest height not nearly 

 attaigning half the length, dorsal margin only very slightly arched, with 

 indication to an angle above the eye, ventral margin distinctly sinuated in 

 front of the middle, anterior extremity obliquely rounded, posterior transversely 

 truncated, with the upper corner somewhat projecting and compressed, lower 

 corner rounded off; seen dorsally, narrow ovate in outline, with the greatest 

 width far behind and about equal to J /3 of the length, side-edges almost straight 

 and parallel in the middle, anterior extremity sharply pointed, posterior more 

 obtuse. Valves rather thin and pellucid, surface smooth and marked with 

 somewhat irregular pittings more scattered in the anterior part and assuming 

 behind a more or less elongate form, edges clothed in front and behind with 

 fine hairs. Anterior antennae with the terminal part about the length of the 

 distal segment of the basal part, last joint rather produced, exceeding in length 

 the preceding one. Last pair of legs with the terminal part about twice as 

 long as that of the 1st pair, and armed at the tip, in front of the apical claw, 

 with 3 small spines. 



Male. Shell rather more elongate than in female and somewhat higher 

 in front than behind, with the supero-posteal corner more projecting. Copul- 

 ative appendages with the anterior lappet of the terminal part acutely produced, 

 posterior shorter and obtuse at the tip. 



Colour yellowish brown, from the dark translucent body; limbs bright 

 yellow. 



Length of adult female 0.70 mm., of male 0.73 mm. 



Remarks. The present species was described as early as the year 1850 

 by Baird as Cythere pellucida, and has been recorded under this name by 

 most subsequent authors. In the year 1889, however, Brady and Norman pro- 

 posed to change the specific name to confusa, because they had found that 

 some specimens in Norman's collection, determined by Baird as C. pellucida, 



