DAPHNELLA. 
109 
with several strong setae, and the whole organ presents a 
curved appearance. In full-grown females (t. XII, f. 3) 
the ovary contains upwards of twenty young, and the ani- 
mals then present a different appearance from those which 
have no ova (t. XIII, f. 1). The young resemble the 
parent from their birth. Twenty-four hours after being 
born they appear as represented in t. XII, f. 4. 
The motion of the Sida through the water is a sort of 
rapid running movement. They are generally inactive, 
and adhere in a peculiar manner by the back of their head 
to the side of the vessel in which they are contained, 
remaining there for hours. They adhere most probably 
in the same way to the weeds in the water where they 
are found, as it is by skimming the stems of the weeds 
that they are detached and caught. They do not appear 
to be numerous in the localities in which I have found 
them, and indeed are of rare occurrence. 
Hab . — Back fishpond at Overstone Park, Northamp- 
tonshire, July and August, 1849 ; ditch near Richmond, 
opposite Isleworth, August, 1849 ; found near Dublin, 
by Professor Allman, W. Thompson, Esq., July 1848. 
Genus 2- — Daphnella. 
Inferior antennae very large ; both branches consisting 
each of only two articulations. 
1. Daphnella Wingii. Tab. XIV, figs. 1-4. 
Carapace elongated, rounded at the back, slightly curved 
at inferior extremity, and having a small mucronation, 
somewhat truncated in front, and of a beautiful, clear, 
crystalline transparency. 
The head is long and narrow. 
Eye (t. XIV, f. 4 c ) large, round, composed of upwards 
of forty crystallines, and nearly filling the upper part of 
the head. 
