ARCHIV FOR MATHEMATIK OG NATÜRYIDENSKAB. B. XVIII. Nr. 3. 



Cladocera. 



Fam. Da/ptmlclae. 



Gen. Daphnia, Müller. 



1. Daphina carinata, King. 

 (PI. 1.) 



Daphnia carinata, King, Papers & Proceedings Roy. 

 Soc. Van Dienien's Land, Vol. II, Part. II, p. 246, PI. I, 

 p. 253, PI. VI. A. 



Specific Characters.— $ Shell, seen laterally, some- 

 what varying in shape, being in some specimens oblong oval 

 and narrowed posteriorly, in others comparatively broader, 

 rounded quadrangular, spine generally rather long and more 

 or less obliquely upturned, denticles of the dorsal margin 

 extending nearly to the cervical region. Head distinctly 

 carinated throughout, the carina being more or less developed, 

 and thereby causing the lateral aspect of the head to be 

 somewhat variable, though it always appears rounded in front; 

 rostrum acute, not deflexed; fornix terminating on each side 

 in a spiniform corner. Eye of moderate size. Antennulæ 

 very small, scarcely projecting beyond the shell of the head. 

 Tail conically tapering, with the posterior edge perfectly 

 straight, anal denticles about 12 on each side, rather small 



