246 On some of the Species of Daphniade 
each two-branched; one branch composed of four, the 
other of three articulations. 
Genus Dapunia. (Miiller.) 
Head produced downwards into a more or less prominent 
beak. Superior antenne, generally small and one-jointed, 
situated under the beak. 
(1.) Daphnia carinata. (Plate I.)—The valves of the 
shell or carapace are oval; nearly colourless; irregularly 
reticulated. The head is large and rounded, particularly 
in the variety marked B. ‘The anterior part generally 
comes to a sharp point. The front view of the head has 
a singularly carinated appearance. 
The superior antennze are very small, hardly to be 
distinguished, except with a high power of the microscope. 
Each consists simply of a thickened lump, from which 
nine seta spring. The inferior antenne are of mode- 
rate size; the articulations rough, with short spines 
irregularly dispersed over them. ‘The sete are short and 
thickly plumose. 
The posterior angle of the shell terminates in a long 
sharp point closely serrated along both sides; the serre 
extending along the dorsal margin half way to the head, 
and along the margins of the valves through a considerable 
portion of their length. They are larger in the young 
individuals than in the older. 
The eye is large. The sixth segment of the body has 
three projections, one directed upwards supporting the 
ova. 
This species in many respects resembles D. Psittacea 
(Barrp). Its greater size—the smallness of the superior 
antennz, and the roundness of head and sharpness of its 
beak—sufficiently distinguish it from the English species. 
