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 CRUSTACEANS a green variety at Roby in August and September, 1851 ; and a male of a very large green variety from a ditch near Seaforth : it was very distinct from that caught at Roby, and much more beautiful';^ D. hircus (Brady), of which the author, Dr. G. S. Brady, F.R.S., remarks, ' I took a few specimens only of this, which appears to be a quite distinct species, in Goat Water, a tarn lying at a considerable elevation on the side of Coniston Old Man ' ; ^ Temora longicornis (O. F. Miiller) from the mussel beds at Piel, a species of which Sars observes that ' it moves in a peculiar revolving manner, and this seems to be the case with all the members of this genus ' ; * and Eurytemora affinis (Poppe), of which Temorella affinis (Claus) is a synonym, noticed by Mr. Thompson in the following terms : ' Length 1*75 mm. A large number of this species were taken by tow-net off the sand-banks at the mouth of the Mersey in 1 886. It was not subsequently recorded in the district until 1891, when the filter-beds of the Bootle Corporation baths were found to be swarm- ing with it. Mr. Ascroft has since sent me specimens found in tidal pools at Lytham. The males I have found are conspicuous by the number of sper- matophores attached to them.'* In 1894 Mr. Ascroft found this species filling the stomachs of fishes only half an inch long.^ The family Cyclopidae appeals in this county for further research. At present it claims the vague Cyclops quadricornis, of which the Fauna of Liverpool^ says in general terms : ' Common in most ponds and ditches ; all the varieties are met with'; C. abyssorun (G. O. Sars), reported by Brady as ' taken in gatherings made by the deep net in Windermere and Coniston Water, but by no means plentiful';'' C. scourfieldi (Brady), of which the same author says, ' My first knowledge of this species was .... derived from specimens which I took myself by moonlight in the surface-net at Coniston, in August, 1883 ; in this gathering it occurred in considerable numbers, as also in a subsequent daylight surface-gathering from the same lake ' ; ^ and recently he writes : ' The form described by me years ago under the specific name scourfieldi has been identified by other authors (Lilljeborg, Herrick, Schmeil) with G. leuckarti (Claus). I am doubtful as to the correctness of this identifi- cation : both Schmeil and Herrick figure, with differences, peculiar pellucid marginal laminae on the last two joints of the larger antennae. I have been unable to detect any such structure in my British specimens of C. scourfieldi, neither does it exist in the Natal specimens nor in others from Ceylon, which I refer to the same species.' ' From these remarks the student will readily infer that a very close attention to details is exacted by the requirements of modern classification. The distribution too of a minute freshwater species over several continents, though by no means unexampled, may still excite some surprise. Concerning ' Cyclops magnoctavus (Cragin) ' Mr. Thompson says : ' One or two specimens of this brackish species were found along with quantities of 'Temorella afiinis and Tachidius brevicornis in tow-net gatherings sent to me by Mr. Ascroft, taken by him in low-water marine pools at Lytham. It is evident that a considerable amount of fresh water finds its way into the Lytham pools.' ^^ This C. magnoctavus is now regarded as a 1 Fauna of Liverpool, 55. ' Nat. Hist. Trans. Northumb. etc. xi. pt. i. loi (1891). 8 Crustacea of Norway, iv. 98 (1903). * Trans. Liverp. Biol. Soc. vii. 182. 5 Op. cit. ix. 107. ^ Op. cit. p. 55. '' Nat. Hist. Trans. Northumb. etc., xi. pt. i. 74. 8 Ibid. p. 76. ' Proc. ZooL Soc. Lond. ii. 1 22 (1904). i" Trans. Liverp. Biol. Soc. ix. 99. 171