218 
BRITISH ENTOMOSTRACA. 
water. For this purpose it curls its body into the form 
of a ball, and then suddenly returning to the straight 
position, springs with a sudden bound from the bottom 
to the surface, falling gradually down again to the same 
place from which it had sprung. 
Hah . — Berwick Bay, 1885, not common. — /^c^rr 
Family 2— DIAPTOMIM. 
Character . — Head in general distinguishable from the 
body, though firmly articulated with the first ring of the 
thorax. Foot-jaws, three pairs, well developed. Legs, 
five pairs ; the last pair differing in structure from the 
others, and differing also from each other in the two sexes. 
One eye; sometimes in male sex pedunculated. Bight 
antennae alone, in the male, furnished with the swollen 
hinge-joint. 
The habits and manners of the animals of this family 
are very similar to those of the Cyclopidse. Some are 
inhabitants of the fresh water, and others are marine. 
The manner of hatching their young, and the changes 
these undergo in their progress to maturity, are very 
similar; only it would appear, from Jurine’s observations, 
that the mother must carry the ova along with her, till the 
young are hatched, whilst, in the Cyclopidae, the eggs may 
be hatched, after they are removed from the mother. 
This family contains three British genera. 
1. Diaptomus. — Flead distinguishable from body. 
Thorax and abdomen each composed of five segments. 
Antennules two-branched. 
2. Temora. — Head consolidated with first ring of 
thorax. Thorax composed of five, and abdomen of three 
segments. Antennules two-branched. 
3. Anomalocera. — Head distinguishable from body. 
Thorax composed of six, abdomen of four segments. 
Antennules not two-branched. 
