On Australian Entomostracans. 57 



Order I. Ostracoda. 



OSTRACODA. LaTREILLE. 



Character. — Body enclosed entirely in a covering of two 

 valves, resembling a bivalve shell; posterior jaws branchi- 

 ferous; no external ovary; feet two and three pairs, adapted 

 for progressive motion. This order contains three families, 

 Cypridm, Cytlteridm, and Cypridiiiadce, I shall confine 

 myself to the first of these. 



Fam. I. Cyprid^. 

 Cypris. Muller et Auctorum. 



Character. — Two pairs of antennse ; superior, long with 

 numerous joints, and a pencil of long filaments ; inferior, 

 stout, and pediform. Feet, two pairs. * 



It would be unnecessary in this place to describe minutely 

 the animals of this family ; such a description has already 

 been, published in the Natural History of the British 

 Entomostraca, one of the publications of the Ray Society, 

 1849, I need therefore but refer to that work, and add a 

 very brief description, laying stress only on those particulars 

 in which the Australian species appear to differ from the 

 European. 



" The body of the animal is completely enclosed within 

 a shell of two valves of a horny cretaceous substance, which 

 in general appearance closely resembles a small mussel :" 

 the body consists of two rounded portions of unequal size. 

 The thoracic, from which spring the antennae, the antennules 

 or rami, the organs of the mouth, and the first pair of feet 

 and the abdominal, from which spring the second pair of 

 feet and the tail, and which contains the generative system. 



* I have copied the above almost verbatim from Mr. Baird's work ; — 

 omitting only the notice of the eye, which the discovery of Newnhamia 

 proves to be a generic, and not a family characteristic. 



H 



