CRUSTACEANS 



of Miiller by observing certain correlated distinctions of a very 

 interesting kind. The species which he retained in Cypris have on the 

 second antennae a pencil of long hairs or plumose seta?, and the species 

 endowed in this way swim freely and rapidly through the water, but 'the 

 others are deficient in this apparatus, and, instead of swimming gaily 

 through the limpid element, crawl in the mud at the bottom of the pools 

 in which they are found, or creep along the aquatic plants which grow 

 there, and if dropped into a glass of water fall to the bottom without 

 being able to suspend themselves for the shortest time.' These, he adds, 

 constitute the genus Candona, which he first published in 1845. 



Cando7ia fabaformis (Fischer) is reported by Brady and Robertson 

 from the river Nene at Peterborough. This bean-shaped Candona attains 

 a length of i mm. in the female, and viz^ mm. in the male, the shell of 

 the latter being described as thin and delicate, pellucid, with yellowish 

 patches ; the posterior portion of the valves marked with three or four 

 long crescentic lines, which correspond in position with the coils of 

 spermatic tubes.' ^ 



Darwinula stevensoni, Brady and Robertson, sole representative of the 

 family Darivinulidce, is recorded from the river Nene, and said to be 

 ' perhaps the most characteristic Entomostracan of the East Anglian Fen 

 district, where it is widely spread, and often occurs in considerable 

 numbers.' ^ 



Metacypris cordata, Brady and Robertson, is found in the river Nene. 

 The specific name refers to the heart-shaped outline of the valves in the 

 female, when viewed from above. The colour is green, with irregular 

 blotches of darker green or black. The length is one-fiftieth of an inch. 



Cytheridea lacustris (G. O. Sars) is reported by Brady and Robertson 

 from the river Nene at Peterborough.^ As might be inferred from its 

 name, it occurs in lakes as well as in rivers. 



All the above mentioned Ostracoda belong to the section or tribe 

 called Podocopa. They and their companions from other groups must 

 be regarded as illustrative samples, not as a detailed catalogue, of the 

 carcinological treasures of this county. 



* Brady and Norman, 'Monograph,' part i. p. 103. ^ Lo(. at. part i. p. 122. 



' Loc. cit. part i. p. 1 76. 



107 



