328 History of British Entomostraca. 
first pair (Fig. 9,) has both stalks divided into three articulations, the 
external () has all three of nearly an equal length, whilst the in- 
ternal (/;) has the first articulation nearly as long as all the three 
of the external together, but the two last are short and inclined out- 
wards. The three other pairs (Fig. 10,) have the internal stalk 
shorter than the external ; both consist of three joints, though Ju- 
rine says the external has five : the last pair are the longest of all. 
The fulcra or supports (Fig. 11,) are situate under fifth segment, and 
consist each of a broad flat body, from one side of which issues an 
appendage or kind of finger furnished with several hairs, the oppo- 
site side being rounded, and also giving off a number of setae. In the 
same place in the male are situate the organs of generation. At the 
base of sixth ring in female are the openings of the canalis deferens, 
and under sixth and seventh segments the adults of same sex carry 
a very singular, horny looking, club-shaped organ, which is fastened 
to the body by a narrow elongated stalk. It is somewhat curved 
and directed backwards, its colour almost always more or less red. 
This organ is not found in the young female, till after she has se- 
veral times laid eggs. Its hardness is greater than that of the shell 
of the animal ; its use is not known. Jurine has seen two in one fe- 
male, one red, the other black. In copulation, the male of this spe- 
cies lays hold of the terminating segment of the tail just above the 
commencement of the long filaments which issue from it, as repre- 
sented by Muller in his plate of this species. 
B. Marine Species, 
4. Cyclops chelifer, Plate IX. Fig. 15-22. Specific Character. Antennis 
brevibus ; capite rostrato ; manibus chelatis ; cauda biloba ; setis duobus 
longitudirie corporis ; ovario unico. 
Synonimes. Cyclops chelifer, Muller, p. 114. tab. xix. Fig. 1 3- 
Cyclops Johnstoni, Baird, Transactions of Berwickshire Naturalists' Club, 
p. 97. plate 2. fig. 4. 
Habitat. Sea shore of Berwickshire, as at Cockburnspath, Berwick bay, &c. 
Description. Body of 4, tail of 6, segments terminating one 
giving issue to two long, linear, finely serrated setae, fully the length 
of the body ; upper or cephalo-thoracic segment of body beaked, 
or having a short conical proboscis in centre. Antennae (Fig. 16) 
short, of about 10 articulations in female at junction of fourth with 
fifth, is a small lateral ring in both sexes. About fifth ring in male 
(Fig. 22) is the swelling, which is in the form of a bulla or bladder, 
followed by the hinge- joint. Antennules (Fig. 17) of two articulations, 
as in minutus ; the first having a shoot sent off from about its cen- 
tre, consisting of two articulations, furnished with several setae ; the 
