A HISTORY OF SURREY 



divided into two tribes. These are called the Onych6poda and the 

 Haplopoda, or the nailed feet and the simple feet, the former having 

 four pairs of feet fitted with a basal maxillary process, while in the latter 

 there are six pairs of feet devoid of such a process. The first tribe is 

 limited to the family Polyphemidae, represented in Surrey by Polyphemus 

 pediculus (Linn.), which the Quekett Club report from Woking and 

 from Richmond Park, 1 Baird having previously recorded it in the 

 following terms : ' Ditch near Richmond, on the banks of the Thames, 

 nearly opposite Isleworth, July. It seems to be very limited in its range 

 of habitat, for though this ditch is frequently filled by the tide from the 

 river, and is fully a mile in length, I have only found it in one spot, not 

 much above twenty yards in extent.' Of this species, notable for its 

 great eye in front and great receptacle for the young to the rear, 

 Dr. Baird remarks that 'the males have never yet been noticed by any 

 observer.' Since however, ' like the Daphnitz, the Polyphemus has, at 

 particular seasons, the ephippium, or saddle, which serves exactly the 

 same purpose as in them,' 2 namely, to shelter the ' resting-eggs,' we may 

 assume that the same rule applies here as with the Cladocera in general, 

 permitting parthenogenetic development for the ordinary eggs, but re- 

 quiring fertilization by the male for those eggs which pass through 

 a probationary or resting period separated from the mother. 



Of its Ostracoda, however well provided with them in reality, 

 Surrey cannot at present greatly boast. Baird describes and figures 

 a new species Cypris gibbosa as taken in 1836 from a 'ditch near the 

 Surrey Zoological Gardens' 8 ; but Brady and Norman say, 'This species 

 is unknown to us. Dr. Baird's description may perhaps be taken to refer 

 either to C.prasina or Cyproisjla-va.'* Cypris reptans, Baird, is recorded by 

 Dr. Baird himself from 'the neighbourhood of London,' 6 and by the Que- 

 kett Club from Richmond Park. 6 Brady and Norman transfer it to a new 

 genus Erpetocypris, so that both by its generic and specific names it is 

 now dubbed as the creeping Cypris. Baird indeed transferred it to his 

 genus Candona, which he established for animals of this habit. He 

 noticed that some species of Cypris were lively swimmers, and that their 

 agility depended on the presence of a bundle of long plumose setae upon 

 the second antennas. For these he retains the generic name Cypris. But, 

 he says, ' the others are deficient in this apparatus, and instead of swim- 

 ming 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 

 constitute the genus Gandona.' 7 In this genus he placed also a species 

 called Candona simi/is, from a 'pond on Clapham Common,' 8 which Brady 



Q. M. C. ser. 2, vol. ii. p. 34, vol. iv. pp. 472, 273, 326. 

 British Entomostraca, pp. 113, 1 14. 



Loc. at. p. 156 ; and Mag. Zool. Bot. vol. i. p. 137 (1837). 

 Trans. Royal Soc. Dublin, ser. 2, vol. iv. p. 78 (1889). 



British Entomostraca, p. 161. 6 Q. M. C. ser. 2, vol. ii. p. 191 (1884). 



7 British Entomostraca, p. 160. 8 Loc. cit. p. 162. 



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