A HISTORY OF NORTHAMPTONSHIRE 



not from canthos, which means a pack-ass, the apple of an eye, or the 

 felloe of a wheel. The specific name of the Northamptonshire species 

 alludes to a character mentioned in the description of the terminal furca, 

 of which Dr. Brady says, ' caudal segments about as long as broad, 

 bearing three stout marginal spines, and two plumose apical sets.' 



Among the little bivalved Ostracoda a few species have been tracked 

 to this county by some of our keenest masters of research, Dr. Brady, 

 Canon Norman, and the late David Robertson of Cumbrae. They are 

 as follows : Prionocypris serrata (Norman). This species, after passing 

 through the genera Cypris and Erpetocypris or Herpetocypris, has recently 

 been placed by Brady and Norman in a new genus, Prionocypris, meaning 

 the Cypris with a saw, so named because the extremities of the valves 

 are more or less denticulately serrated. Brady and Robertson are the 

 authorities for its capture in the river Nene at Peterborough.^ 



Cypridopsis mwtoni, Brady and Robertson, is also found in the river 

 Nene. It has a coarsely hispid surface, is dull green in colour, and 

 attains a length of '85 mm., that is, about a thirtieth of an inch.* 



Cypridopsis variegata, Brady and Norman, from the river Nene at 

 Peterborough, was long left undescribed, because of its close resemblance 

 to the preceding species, but its valves are less uniform, its length is only 

 •55 mm., little over a forty-fifth of an inch, and at least in some speci- 

 mens the ground colour is yellowish, and it is ornamented with black 

 bands.' 



Candonopsis kingsleii (Brady and Robertson), taken in the river Nene 

 at Peterborough, was transferred from Baird's genus Candona to a new 

 genus Candonopsis by the Bohemian writer Vavra, from whom Brady and 

 Norman quote the following generic characters, ' Antennae six-jointed, 

 with two peculiar sense organs between the fourth and fifth joints. 

 Mandible palp very long. Second maxills with a trisetose branchial 

 plate. Caudal rami slender ; seta of the dorsal margin absent.' * These 

 characters are taken from the male sex alone. 



Candona Candida (Miiller), of the variety tumida, is mentioned by 

 Brady and Norman as being found in the river Nene.* This variety, 

 they say, ' is much shorter and stouter than the typical form,' and in 

 regard to distribution they observe that ' the ordinary form of C. Candida 

 occurs commonly in ponds and ditches ; the variety tumida is most 

 common in rivers and dykes subject to tidal influence.' In Candona, as 

 defined by Professor Sars, the second antennae are four-jointed in the 

 female, five-jointed in the male, with two sensory spines on the ante- 

 penultimate joint. The mandibular palp is not very long, and the 

 caudal rami have a slender dorsal seta.* Baird explains that he was 

 induced to separate this genus from the old comprehensive genus Cypris 



1 Brady and Norman, 'A Monograph of the Marine and Freshwater Ostracoda of the North 

 Atlantic and of North-Western Europe,' part i., Trans. R. Dublin Soc, ser. 2, vol. iv. p. 87 (1889) ; and 

 part ii., in ser. 2, vol. v. p. 724 (1896). 



* hoc. cit. part i. p. 90 ; part ii. p. 725. * Loc. cit. part i. p. 102 ; part ii. p. 731. 



^ Loc. cit. part i. p. 91 ; part ii. p. 725. ^ Loc. cit. part i. p. 98. 



^ G. O. Sars, Ostracoda Mediterranea, Arch. Naturv., vol. xii. p. 278 (1888). 



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