IV. Trenton Limestone Edrioasters. 1914 115 



IV. The Edrioasters of the Trenton Limestone. 1 

 [Part I.] 



[Geol. Mag., N.S., Dec. VI, Vol. I, pp. 115-125, Pis. X, XI, XII ; 

 March, 1914.] 



Previous History. 



JfiDRI PASTER higsbyi was first made known by E. Billings 

 in June, 1854, 3 and was referred by him, though with some 

 doubt, to Agelacrinites. He gave no specific name, but regarded 

 his fossils as identical with the specimen found by Bigsby at the 

 Chaudiere Falls and described by G. B. Sowerby in 1825 (see 

 Study III), and as "almost identical with A. Buchianus" of Forbes, 

 1848 (see Study II). This series of papers by Billings contains 

 several important observations and reasonings not reproduced in those 

 later more official publications of his to which alone subsequent 

 writers seem to have gone for information. From the original account 

 it is clear that the specimens there called Agelacrinites were the same 

 as those which Billings described in 1857, under the name Cydaster 

 higsbyi} The misapprehension that caused Billings to apply to his 

 new species the trivial name higsbyi has already been dealt witli in 

 Study III; the .species has nothing to do with the specimen found 

 by Bigsby. In 1858 Billings discovered and pointed out his error, 

 and, realizing further that the generic name Ct/claster had been taken 

 by G. Cotteau for a sea-urchin a few months before his own use of it, 

 he redescribed the species under the name Edri<>aster higsbyi. 5 The 

 independence of the genus itself was denied in I860 by E. J. Chapman, 

 who referred the species back to Agelacrinites. 6 The textbook 

 writers, however, generally accepted Edrioaster, and no change was 

 made in either name or description until Professor Haeckel in 1896 

 thought fit to alter the name to Edriocystis? Neither the nomen- 

 clatoral nor the taxonomic vagaries of Professor Haeckel won any 

 favour, and it is needless to allude further to him or to other writers 

 who shared his ignorance of the facts but not his imagination. In 

 that category I do not include Professor 0. Jaekel, but even he, in his 

 Stammesgeschickte der Pelmatozoen (1899, p. 46), contented himself 

 with the information and figures published by Billings in 1858, apart 

 from such hints as he could glean from the manuscript of my then 

 forthcoming Study II. 



1 Plates X and XI of the present Study were drawn in 1900, and diagrams 

 made from the specimen represented in Plate X have been published by me in 

 1900, 1901, 1902, and 1911. The completion of the present paper has 

 unfortunately been delayed by the pressure of official duties and other 

 scientific work. 



3 Canad. Journ., vol. ii, pp. 271-4, figs. 10-12. 



4 Eep. Progress Geol. Surv. Canada, 1853-6, p. 293, Toronto, autumn of 

 1857. 



5 Canad. Org. Rem., dec. Ill, p. 82, pi. viii, figs. 1, la, 2, 2a, June, 1858. 



6 Canad. Journ., N.S., vol. v, p. 364. 



7 " Amphorideen und Cystideen," pp. 117-8, Festschr. f. Gegenbaur, 1896. 



