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 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. ' Loc. cit. part i. p. 1 76. 107
 * Brady and Norman, 'Monograph,' part i. p. 103. ^ Lo(. at. part i. p. 122.