120 BlUTISH ENTOMOSTRACA. 



a point near the root of the antennae, and ahnost upon the 

 extremity of this point is situate the black spot in front of 

 the eye. A short distance from this the body has an in- 

 dentation, in which, or rather on its edge, is situate the 

 eye, ah'eady described. It then takes a round turn, the 

 edge of which is more or less crenated, and from it the 

 muscles attaching the body to the shell arise. It now 

 turns inwards for a short distance, and then bulges out- 

 wards again towards the posterior edge, terminating by a 

 joint in the abdomen.*" The space left where the body 

 turns inwards, between it and the shell, is the matrix, 

 or place where the animal deposits its ova, and where the 

 young remain till ready to be extruded ; and immediately 

 above this is situate the heart. 



The abdomen (t. XV, f. Ik) in all the species I have 

 examined is connected to the body by an articulated joint, 

 differing in this very particularly from the Daphniadse. 

 At this joint we see two setse arise, which in some species, 

 as in the Eurycerms lamellatus, are beautifully plumose, 

 and of considerable length. The abdomen is then pro- 

 jected upwards, being always within the shell v/lien the 

 animal is at rest. It terminates in two or more hooks, 

 the use of which seems to be to assist in cleaning the in- 

 terior of the shell, as the abdomen is flexible, and can be 

 extended at pleasure to a considerable extent beyond the 

 carapace. In one or two species it is remarkably long, as 

 in the Ccauptocercus macrourus, and is extremely flexible, 

 the motion of this organ being evidently of great use to 

 the animal in assisting and regulating its movements. A 

 little beyond this joint is placed the anus, or termination 

 of the alimentary canal. 



The feet are five pairs in number (t. XV, f. 1 e-i) ; the 

 first pair are the largest, and consist each of a fleshy sort of 

 body, bent a little, strongly ciliated on its upper edge, and 

 fmnished at its extremity with five long and strong seta?, 

 which in general project a little beyond the edge of the 



* The body, as above described, is particularly well seen in the Acroperm 

 harp<JE. 



