G. O. SARS. M.-N. Kl. 



Cladocera. 



Farn.: Daphnidæ 



Gen.: Daphnia, Müller. 



I. Daphnia Thomsoni, G. O. Sars. 



DapJinia similis, Thomson, Trans. N. Zeal. Institute, Vol. XVI, p. 240, 



PI. XIII, figs. 6—9 (not Claus). 

 Daphnia Thomsoni, G. O. Sars, Contributions to the knowledge of the 



Fresh-water Entomostraca of New Zealand p. 5, PI. I. 



Of this species, first detected by Mr. Thomson, and recently described 

 and figured by the author in his above-quoted paper, several specimens 

 were raised in one of my aquaria. The specimens exactly agreed with 

 the New Zealand form, and grew to a rather considerable size, the largest 

 specimen measuring in length, without the spine, 3,50 mm. 



2. Daphnia. dolichocepliala, G. O. Sars, n. sp. 

 (PI. I.) 



Specific Characters. Carapace in female, seen laterally, oblong oval, 

 in male considerably narrower, dorsal edge spinulose throughout, the 

 spinules being in some cases even continued on the head, spiniform process 

 slightly upturned and of somewhat variable length. Head in female of 

 moderate size, and defined from the carapace dorsally by a shallow sinus, 

 seen laterally, of a somewhat unusual form, its dorsal part being gib- 

 bously produced and scarcely at all keeled, anterior edge obliquely de- 

 clining, and forming with the straight ventral edge a more or less pro- 

 nounced angular bend, rostral projection short and blunted. Fornix 

 very prominent, and terminating on each side in a rectangular corner. 

 Head in male comparatively smaller and more regularly rounded in out- 

 line, with the rostral projection obsolete. Eye well developed, occurring 



