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
