On Australian Entomostracans. 65 



for several months, and in the autumn they all disappeared ; 

 but in the winter a multitude almost suddenly started 

 into life. In their occupation as scavengers, they materially 

 assist in keeping their habitation in proper order. 



Locality ; — Ponds every where. 



Var. faj Castania pond : — at Varroville, near Denham 

 Court 



Var. fhj Brunnea pond : — in Government Domain, 

 Sydney. 



7. G. lateraria. PI. X. G. 



Shell clavate. The dorsal margin being straight poste- 

 riorly and the ventral margin deeply sinuated. The an- 

 terior extremity is the larger, and is much rounded. Shell 

 greenish, pilose. 



Locality ; — Pond in a Brickfield near Sydney. 



I have received it, with Cypris Stobarti, from Moreton 

 Bay. 



The preceding seven species are able to swim freely 

 through the water. The three following are indeed pro- 

 vided with the long hairs on the rami, which distinguishes 

 the genus Cypris, but they are weak ; and in consequence of 

 the small size of the bodies as compared with the shells, 

 they are hardly able to swim at all. Thus they lead into 

 the next genus, 



8. C. Sydneia. PL X. M. 



Shell oval, both ends being nearly alike ; the ventral edge 

 is nearly straight. The valves are very convex, polished, 

 yellowish, and almost opaque. The animal can swim a 

 little, but not in a horizontal line, and cannot at all raise 

 itself in the water. It is generally seen crawling about on 

 the mud, or at times half buried in it in company with 

 several of its own species. 



Locality ; — a swamp near Wooloomooloo Bay, Sydney. 



I 



