216 
BRITISH ENTOMOSTRACA. 
Genus 4 — Alteutha.* 
Cyclops, Baird, Mag. Zool. and Bot., i, 1837. 
Alteutha, Baird, Trans. Berw. Nat. Club, ii, 155, 1815 ; 
Ann. and Mag. Nat. Hist., xvii, 416. 
Character . — Foot- jaws small, simple ; body flat. Two 
strong falciform appendages from the fifth segment of the 
body. 
Cyclops depressus, Baird, Mag. Zool. and Bot., 331, t. 10, f. 9-12, 
1837. 
Alteutha depressa, Baird, Trans. Berw. Nat. Club, ii, 155, 1845 ; 
Ann. and Mag. Nat. Hist., xvii, 416. 
The body is depressed, flat, and broad, differing in this 
respect very much from all the other genera described. 
The thorax is composed of four segments, the first of 
which contains the head consolidated with it, and is much 
the largest, being more than equal to the three succeeding, 
and having the upper part projecting in a short obtuse 
point. 
The abdomen consists of five segments, and is about 
one third the length of the body ; the terminating seg- 
ment having on each side a small lobe, from each of which 
issues a moderately long seta. 
The eye is situated rather lower down than usual in the 
other species of this family, and is of a fine ruby colour. 
The antennae are short, strong, subcylindrical, setiferous, 
and divided into six or seven articulations ; the first three 
of which are the largest, the last four being smaller and 
shorter. In the female we find a lateral ring at the junc- 
tion of the fourth and fifth joints. The swelling, in the 
male, is situated in the fourth, followed by the hinge-joint, 
and terminated by a hook. The antennules are of two 
articulations, the latter being terminated by four short 
* “Alteutha,” the Town of the Tweed. 
1. Alteutha depressa. Tab. XXX, figs. I, 2 
