202 MR. LUBBOCK ON SOME FRESHWATER ENTOMOSTRACA. 
the four terminal setze, the inner one is about twice as long, but no stouter than the outer. 
'The two great medial setze do not differ much in length, and are about twice as long as 
the lamella. 
Male. The male is altogether slimmer than the female. 
The second pair of antennz and the parts of the mouth resemble the corresponding 
organs in the female. 
The abdomen is longer and thinner than in the female; it is four-jointed, and the 
segments diminish progressively in size, the first being but little bigger than the second, 
while in the female it is as large as the other three put together. The caudal lamelle 
also and the setze resemble those of the female, but that the two larger terminal setze are 
more unequal. 
The posterior legs are in the form of a simple lobe, bearing three sete, of which the 
one on the outside is the largest, and that on the inner side is the smallest. 
The egg-bags are at first greenish, but gradually become light pink. 
Common in a pond on Farnborough Common in Kent, May 1861; and also in a 
horse-pond at Reigate, in July; at Chiselhurst Common, in February, March, April, and 
September. 
The male seizes hold of the penultimate legs of the female with his prehensile antenne. 
. This species may of course be at once distinguished from all those with less than 
seventeen segments to the anterior antenne ; from C. coronatus and C. tenuicornis it may 
be known by the shortness of the antenns and the form of the posterior legs; C. pen- 
natus differs in the length of the antenns, and in having the caudal setze remarkably 
plumose; C. viridis, C. crassus, C. brevicornis, and C. Leuckarti in. the shortness of the 
caudal lamellz ; and the two latter, as well as C. bicuspidatus and C. gigas, in the form of 
the posterior legs; C. strenwus and C. vernalis (if S. Fischer’s figures are quite correct) 
in the setze of the caudal lamellze and of the anterior antenne ; C. furcifer has narrower 
and more elongated lamellz, and the caudal setze, as well as those of the anterior antennze, 
are unlike those of the present species. Finally, C. brevicaudatus is described by Claus 
as having the second segment of the posterior legs bisetose, and the caudal setze little 
longer than the lamelle. | 
CYCLOPS TENUICORNIS, Claus, Z. c. p. 31. Antenne primi paris septendecim-articulate, 
elongate ; ultimi tres annuli tenuissimi, cristam simplicem gerentes. Abdominis 
segmenta in longitudinem extensa. 
Chiselhurst, in June and July. 
This species is very nearly allied to C. coronatus, if indeed distinct. 
CYCLOPS CANTHOCARPOIDES, Fischer. 
This species may at once be known by its having only ten segments to the anterior 
antennz, which are very short, and do not even reach to the end of the first cephalo- 
thoracic segment. The arrangement of the caudal sets gives it the look of a Cantho- 
carpus. The fourth abdominal segment is short; one of the two terminal sete of the 
abdomen is much longer than the other, and the lateral ones are short. 
Chiselhurst. 
