530 Dr. H. Woodward — On the Genus Cyclus. 



I. — Contributions to our knowledge of the Genus Ctclus, from 

 THE Carboniferous Formation of various British Localities. 

 By Henry Woodward, LL.D., F.E.S., Pres.Geol.Soc, 

 of the British Museum (Natural History). 



(PLATE XV.) 



THE curious little shield-like Crustaceans, known under the 

 generic name of Cyclus, were first noticed by de Koninck in 



1841, and have been subsequently figured and described by various 

 authors, but their exact systematic position has never been clearly 

 understood owing to the absence of appendages or other indications 

 by which their affinities might be satisfactorily ascertained. 



In 1868 I gave a description, with figures, of two species : ^ 

 one of which, the Cyclus radialis, had been previously noticed by 

 de Koninck '^ and Piiillips ^ ; the other, C. BanTcini, was then first 

 made known. 



In 1870, under the title of " Contributions to British Fossil 

 Crustacea,"* I redescribed the above-named species, and added Cyclus 

 bilobatus, C. torosus, G. Jonesianus, C. WrigJitii, C. Marknessi, C. 

 [Halicyne) laxus,^ C. (Halicyne) agnotiis.^ 



The next record of the genus is to be found in the fifth part of my 

 Monograph of British Fossil Crustacea ^ of the order Merostomata, 

 which records and figures the then known seven British species of 

 Cyclus, but adds no new forms. 



In 1883 Mr. B. N. Peach, F.E.S., L. and E., F.G.S., published 

 an account of Cyclus testudo, from the Carboniferous series of Lang- 

 holm,'' to which reference will again be made later on. 



In 1893 I noticed a new British species of Cyclus,^ discovered by 

 Mr. George Scott in the " Gannister seam " of the Lower Coal- 

 measures, Old Clough Colliery, Bacup, Lancashire, which I named 

 Cyclus ScottL 



In the same year Mr. F. E. Cowper Keed, B.A., F.G.S., of Trinity 

 College, Cambridge, gave a description of what he deemed to be 

 probably a new species of Cyclus,^ from the Carboniferous Limestone 

 of Settle, Yorkshire, near to, but not identical with, C. Sarhnessi, 

 which he named C. Woodwardi. 



1 British Association Eeports, Norwich, 1868, 4th Eeport on Fossil Crustacea, 

 pp. 72-75, pi. ii. figs. 1 and 2. 



^ L. G. de Koninck, Descript. des Animaux Foss. Terr. Carb. de Belg. Liege, 



1842, p. 591, pi. lii. 



3 J. Phillips, Geol. Yorksh. vol. ii. p. 240, t. xxii. fig. 25, 1829. 



* Geol Mag. 1870, Vol. VII. PI. XXIII. Figs. 1-7, pp. 554-560. 



^, ^, These last-named species are not British, and had been previously described 

 by Prof. Hermann von Meyer, in the Palajontographica, 1847, vol. i. p. 134, under 

 the genus Salicyne. They are from the Muschelkalk of Eottweil in Germany. 

 Goldfuss originally figured Halicyne as Olenus serotinus (Petref actenkunde) , after- 

 wards von Miinster referred it to Limulics (Beitrage, 1841, Bd. i. t. v. f. 1). 



^ Palajontographical Society, 1878, vol. xxxii. pp. 248-255, pi. xxxii. figs. 42-49. 



■^ See Trans. Eoy. Soc. Edinburgh, 1883, vol. xxx. pi. xxviii. figs. 9-9^, p. 227. 



8 See Geol. Mag. 1893, Decade III. Vol. X. (Woodcuts A, B), p. 28. 



9 Ibid. pp. 64-66 (with a Woodcut). 



