208 
BRITISH ENTOMOSTRACA. 
to a female, and have never seen an adult without it, as 
the female has it constantly attached, though the young 
in the ova are ready to be hatched. It is so hard and 
horny too, and differs so much in texture and appearance 
from the spermatic tubes found in Diaptomus, being too 
solid to contain any soft matter, or to form a hollow tube, 
that I am much inclined to doubt the accuracy of Siebold’s 
conjecture, and to believe that the true use of these organs 
is still unknown. 
In copulation, the male of this species lays hold of the 
terminating segment of the abdomen of the female, just 
above the commencement of the long filaments which 
issue from it. 
Hah . — Ponds and ditches of fresh w^ater, all the year 
round ; common. 
2. Canthocamptus Stromii. Tab. XXVII, fig. 3, 3 a . 
Cyclops Stromii, Baird, Zool. and Bot., i, 330, t. 9, f. 23-25, 1837. 
Cyclops brevicornis, Baird, Trans. Berw. Nat. Club, i, 97, 1835. 
Canthocarpus Stromii, Baird, Trans. Berw. Nat. Club, ii, 154, 1815. 
Nauplius Stromii, Philippi, Wiegm. and Erichs. Archiv,1843, p. 69. 
The thorax and abdomen consist of ten segments, 
gradually tapering to the extremity, without any decided 
difference between them. The first segment, consolidated 
with the head, is the largest, and is furnished with a 
conical beak ; the last segment terminates in two lobes, 
which give issue to two se tae. These are much shorter 
than those of the preceding species, being scarcely half 
the length of the body. 
The antennae are composed of eight short articulations, 
and at the junction of the fifth with the sixth they have 
a lateral joint. In the male, the swelling and hinge-joint 
are as in the preceding species. Each of the articulations 
of the antennae throws forward one or two short setae. 
The antennules are formed of two articulations, the 
second being terminated by about four somewhat long 
filaments. The mandibles were not seen. The posterior 
