62 G-. O. SAKS. [No. 7. 



over in its original dried state; and in this aquary the conditions 

 seemed to be rather favourable for the growth of the present 

 species, numerous specimens, partly of much larger size than 

 those previously observed, having developed in the course of the 

 summer. All the specimens were however females, propagating 

 in the usual manner by summer-eggs. In August I had to leave 

 Christiania for some time, and on my return the water was 

 wholly evaporated in the aquary. Of course I have not yet been 

 enabled to observe either the winter-eggs, or any male specimen. 



Occurrence. — The mud from which I raised this species 

 was collected from a single locality, a fresh water lagoon — 

 called Malchi — 3 miles from Gracemere. 



11. Alona clathrata, n. sp. 



(PI. 6, figs. 7-10). 



Specific Characters. — Carapace of adult female, as seen 

 laterally, rather short, rounded quadrangular in form, posterior 

 extremity truncated, with the upper angle distinct, lower rounded 

 off; inferior edges of valves slightly ascending anteriorly. Head 

 semierect, hood-like, terminating in an acute rostrum projecting 

 beyond the inferior edges of the valves. Carapace of male com- 

 paratively narrower, with the dorsal edge much less arche I 

 Surface of shell densely reticulate, the reticulation more especi- 

 ally very distinct in female specimens with winter-eggs. Ocellus 

 nearly as large as the eye. Antennulae slender conical, almo 

 reaching to the tip of the rostrum, not very much larg er 

 male. Tail of female rather short and broad, apex obliqlW ; j 

 truncate, with the posterior corner distinctly angular; suptf 



angle projecting; outer part of dorsal edge straight ^ 

 with a double row of very short but strong denticles of eq«^ 

 size; no lateral rows of spines present; caudal claws 

 tively rather short, secondary basal denticle exceedingly sn 



and armed 



