THE 



GEOLOGICAL MAGAZmE. 



NEW SERIES. DECADE IV. VOL. VII. 



No. v. — MAY, 1900. 



L-StUDIES in EdUIOASTEROIDKA. II. EDBIOASrER BUCHIANUS 



Forbes sp. 

 By F. A. Bather, M.A., F.G.S. 

 (PLATES VIII, IX, AXD X.) 



IN 1848, under the name Agelacrinites Buchianus, Edward Forbes 

 introduced to science -one of the most remarkable Cystideans 

 as yet discovered in British strata." His description and figures 

 published in his memoir "On the Cjstidefe of the Silurian rocks 

 of the British Islands (Mem. Geol. Surv. Gt. Brit. II pt ii • see 

 pp. 519-523, and pi. xxiii), have not proved fully 'intelligible to 

 subsequent workers, even to those who have had the fossil before 



St ,,^,",^°;'^"^,^^^^^^^ On the Fossils 



of North Wales," to - The Geology of North Wales " by A. C. Ramsay 

 (Mem. Geol Surv. Gt Bnt., Ill, 1st ed., 186G), criticised a little, but 

 Illuminated less; while the same Appendix in the second edition, 

 1881, though "greatly enlarged and partly rearranged by Robert 

 Etheridge, F.R.&., merely introduced verbal alterations into Salter's 

 account. 



Allusions to this fossil by writers who have not themselves 

 examined it serve chiefly to show the need that exists for a fresh 

 description. Through the kindness of the Director-General of the 

 Geological Survey and of Mr. E. T. Newton, to whom my sincere 

 thanks are here offered, the original specimens were placed at 

 my disposal for several months. About two years ago the first 

 draft of this paper and some of the illustrations were sent to 

 l)r. Otto Jaekel in Berlin, and have been utilised on pp 41-4(j 

 ? rp,^^ splendid volume "' Stammesgeschichte der Pelmatozoen. 

 1. 1 hecoidea und Cystoidea " (1899). Thanks to Mr. J. F. Whiteaves 

 and the Director of the Canadian Geological Survey, I subsequently 

 learned the true structure of Edrioaster Bigshyi, which was unknown 

 to Dr. Jaekel when he wrote the pages referred to. Hence some 

 interpretations in the present account differ from those given 

 by Dr. Jaekel. They agree, however, with the statements in 

 chapter xu-The Edrioasteroidea— of "A Treatise on Zooloo-y, 

 l^art III, The Echinoderma," edited by Professor E. Ray Lankesler 



DECADE IV.—VOL. VII.— NO. V. I3 



