250 On sone of the species of Daphniade 
the front of the head near the centre. Inferior antenne 
very large, and generally fleshy at the base. 
(1.) Moina lemne. (Plate IV).—Head round, giving 
the animal a singularly graceful outline. Carapace oval, 
smooth. There are setz in the anterior surface and margin 
of the valves as far as the ventral angle. | 
Superior antenne long, with a few minute setz springing 
from the upper edge. The basilar joint of the inferior 
antennz is stout and fleshy, having two sete springing 
from a crenation on the outer side, and a short seta or 
spine from the top of the joint at the immer edge. A 
similar short spine springs from the extremity of the 
second joint of the anterior branch, and another from the 
fourth joint of the same. Each branch has five jointed 
and plumose sete. | 
Near the base of the superior antennz is a small black 
spot. 
The first pair of feet are replaced by an organ apparently ) 
adapted for clasping the roots of the lemnz and fibres of 
conferve, among which I found it. It consists of two 
fleshy hooks, one of which is partially moveable. The use 
which I have assigned to it is conjectural. I have almost 
doubted whether the possession of this organ does not 
remove it from the genus Mozna. 
The extremity of the abdomen is like that of Daphnia, 
except that it has no processes, nor any circle of spines 
round the anus. 
The eye of the foetus is double. But the two eyes 
unite, and in the adult the eye is single and nearly round. 
In some specimens, however, there is a notch at the bottom 
of the eye (seen when the animal is viewed in front), a mark 
of its former divided state. 
