127 



49. Dolerocypris fasciata <O. Fr. Mtiller). 



(PI. LVIIl). 



Cypris fasciata, O. Fr. Mtiller, Entomostraca, p. 53, PI. IV, figs. 1 3. 

 Syn : Monociilus fasciatus, Jurine. 

 Cypris ephippiata, Kocli. 

 Herpetocypris fasciata, Brady & Norman. 

 ,, Stenacypris fasciata. G. O. Sars. 

 ,, Eucypris fasciata, Daday. 



Specific Characters. Female. Shell, seen laterally, narrow oblong in 

 shape, greatest height in the middle and only slightly exceeding 1 /^ of the 

 length, dorsal margin evenly arched in the middle and sloping slowly to each 

 extremity, ventral margin almost straight, anterior extremity narrowly rounded 

 off at the end, posterior rather narrower and drawn out to an obtuse corner; 

 seen dorsally, narrow fusiform in outline, with the greatest width not fully 

 attaining Va of the length, both extremities gradually narrowed and nearly 

 equal. Surface of shell smooth and finely hairy; right valve with a well 

 defined marginal area in front, wanting on the left valve. Caudal rami straight, 

 sublinear in form, with the dorsal edge very finely ciliated in its outer part, 

 distal claw fully half the lenght of the ramus and almost twice as long as the 

 proximal one, both armed behind with a double row of coarse denticles; dorsal 

 seta so very small as easily to escape attention; apical bristle well developed. 



Colour light olivaceous, with a very conspicuous dark, saddle-like band 

 across the back behind the ocular region, extending down to about the centre 

 of the shell. Ripe ova and ovarial tubes shining through the shell with a 

 bright orange hue. 



Length of adult female 1.60 mm. 



Male unknown. 



Remarks. The present form is readily recognised from any of our other 

 fresh water Ostracoda by the extremely narrow and elongate shape of the 

 shell and, when examined in the fresh state, also by its characteristic colour. 

 It was formerly erroneously referred by me to the genus Stenocypris, from 

 which it in reality differs essentially in several respects. Nor can it, as done 

 by Brady and Norman, be referred to the genus Herpetocypris, as it is by no 

 means devoid of swimming power. 



Occurrence. I have only met with this form in 2 localities of our country, 

 viz., in a small grassy pool at Lysaker and in a similar pool at the border of 

 0stensj0 lake, both localities in the neighbourhood of Christiania. The 



