108 
BRITISH ENTOMOSTRACA. 
The second has three plumose setae springing from its 
inner edge, each arising from a small projection, and 
furnished with a joint about the middle of their length ; 
and one short simple spine from outer angle at the an- 
terior extremity. The third has seven similar setae, four 
on the inner edge, and three at the extremity, besides 
one short simple spine at the outer angle. The inner 
branch has only two joints, the first much the longer of 
the two, and having at its extremity or inner edge one 
short simple spine, and one long seta, the second or 
terminal very short, and having four long plumose setae 
from its upper edge. 
The mandible (t. XIII, f. c ; t. XII, f. 8 a,/) is similar 
to that of Daphnia Schcefferi, and has a row of cutting teeth 
on its edge. The labrum (t. XII, f. 3 a ,g) is like that of 
Daphnia, and is provided with a strong muscle. The 
intestinal canal is large. The oesophagus is in form of a 
narrow, slightly-curved canal, which terminates a little 
below the eye in a large cul-de-sac , the commencement 
of the stomach (t. XII, f. 3 a, e). There does not appear 
to be any organ corresponding to what has been described 
in Daphnia as the caecum. The feet are six pairs in 
number, and differ from those in the Daphnina, and also 
from each other. The first pair (t. XIII, f. d) consists of a 
main stalk of two articulations, one of which has four 
setae, the other seven. From the inner edge springs a 
large branchial plate provided with about thirty filaments, 
and from its upper part a smaller plate arises furnished 
with nine or ten short filaments, and one longer and 
plumose. The four succeeding pairs are more like each 
other, but differ somewhat from the first pair. They 
each (t. XIII, f. e,f) possess a small triangular plate fixed 
upon the edge of the main stalk, and taking the place of 
the setae which are found in the preceding. The smaller 
branchial plate is shorter, broader, and square-shaped, 
and the branchial filaments of both plates are shorter. 
The sixth pair (t. XIII, f. cj) differs from all the others. 
Each foot consists of three articulations, each furnished 
