CRUSTACEANS 



neglected by our English zoologists ; and yet I am not aware that any 

 one has written on the freshwater Cyclopidae of Great Britain since the 

 appearance of Dr. Baird's work, or has attempted to compare our 

 English forms with those described by the foreign carcinologists, and 

 especially by Claus and Fischer." Since then the comparison has been 

 carried further back to the works of Koch and Jurine, with the result 

 that specific names accepted in 1863 have undergone various dis- 

 placements. Beginning with the species of Cyclops that have the first 

 antennae seventeen-jointed, we find that C. coronatus^ Claus, recorded by 

 Lubbock from Chislehurst, is transferred by Brady to C. signatus, Koch, 

 but Mr. Scourfield, who has found the same species at Keston, adopts 

 for it the admittedly earlier name, C. albidus (Jurine). This species has 

 a serrated rib or crest on the last joint of the first antennae, while C. 

 tenuicornis, Claus, recorded by Lubbock from Chislehurst, with the 

 remark that ' this species is very nearly allied to C. corotmtus, if indeed 

 distinct,' has the crest simple. The smooth crest, however, is now 

 supposed only to represent a slightly earlier stage in the animal's 

 development.^ C. strenuus, Fischer, is reported by Scourfield from 

 Hayes and Keston. For this species the same name is adopted by 

 Brady, though he gives as synonyms the earlier names, Monoculus 

 quadricornis rubens, Jurine, and Cyclops pictus, Koch, as well as the later 

 C. bre-vicaudatus, Claus, which Lubbock found 'common at Chisle- 

 hurst,' and C. clausii, Lubbock, which that author found ' common in 

 a pond on Farnborough Common in Kent, May 1861 ; and also in a 

 horse pond at Reigate, in July ; at Chislehurst Common, in February, 

 March, April, and September.' Lubbock mentions that ' the male seizes 

 hold of the penultimate legs of the female with his prehensile antennae,' 

 and that ' the egg-bags are at first greenish, but gradually become light 

 pink.' By Scourfield C. leuckarti, Claus, is reported from Keston ; 

 C. dybowskii (Lande), from Hayes ; C. viridis (Jurine), var. gigas^ Claus, 

 from Hayes, Keston, Gravesend and Chislehurst, and C. bicuspidatus, 

 Claus, var. lubbockii, Brady, from Gravesend. C. brevicornis, Claus, 

 recorded by Lubbock as ' common in ponds at Farnborough and 

 Chislehurst, in Kent, etc.,' is now identified with C. viridis (Jurine). 

 Of the species which have the first antennae twelve-jointed, C. serrii- 

 latus, Fischer, is recorded from Kent by Lubbock, who mentions it as 

 one of the smallest species of the genus, apparently hardy, and living 

 well in confinement. By Scourfield it is reported from Hayes, Keston, 

 Gravesend and Orpington. C. phaleratus, Koch, with ten-jointed first 

 antennae, is recorded by Lubbock from Chislehurst, but under the later 

 name C. acanthocarpoides, Fischer. C. Jimbriatus, Fischer, with the first 

 antennae only eight-jointed, is reported by Scourfield from Keston. Of 

 the family Diaptomidae Diaptomus castor (Jurine) and D. gracilis, Sars, 

 are reported by Scourfield from Chislehurst, and had been previously 

 recorded from Kent by Lubbock, who supposing the second species 



' Transactions Linn. Soc. London, xxiv. pt. 2, 197 (1863). 



» See Brady, Natural History Transactions, Northumberland, etc. xi. 72 (1891). 



259 



