180 G. STEWARDSON BRADY. 



for much difference in minor distinctive characters, and it 

 seems very likely that the specimens here noticed are not 

 quite fully grown. The most characteristic form of the 

 Richmond specimens is represented in fig. 8. 



Genus Ceriodaphnia Dana. 

 Ceriodaphnia natalis sp. n. PI. XXXII, figs. 3-7. 



Carapace of female seen laterally tumid, rounded, sub- 

 quadrangular, postero-dorsal angle much produced and 

 sharply pointed, both dorsal and ventral margins strongly 

 convex (fig. 5), seen dorsally (fig. 6) the outline is ovate, 

 rather acutely pointed behind, about twice as long as broad ; 

 shell marked throughout with minute and closely-set circular 

 punctations; antennules short, club shaped; eye moderately 

 large. Post-abdomen with a small dorsal process, terminal 

 portion rounded and rather wide, anal spinules eight or nine on 

 each side, gradated in size from the middle to each end of the 

 series (fig. 7), terminal claws bearing four short spinules near 

 the base ; head much depressed, separated from the body by 

 a deep dorsal depression, rounded and prominent inferiorly. 

 Length, 0-77 mm. 



The carapace of the male (fig. 3) seen laterally is much 

 narrower, and almost quadrangular, the dorsal and ventral 

 margins almost straight and sub-parallel ; eye rather larger 

 than in the female ; antennule large, bi-articulate, projecting 

 beyond the head, bearing a large setiform flagellum and a 

 brush of about four small sensory sette. Length, 0"66 mm. 



This species was found rather plentifully in a netting from 

 Richmond. It seems to be quite distinct from any other 

 described form. 



Genus Alona Baird. 



Alona glabra G. 0. Sars. 



Alona glabra Sars, 'Fresh-water Entomostraca of South 

 America/ pt. I " Cladocera," p. 55, PI. IX, figs. 6, 6a. 



