6 



BBITISH FOSSILS. 



of tubercles at the upper part as those from Yorkshire, while the 

 granules are also less conspicuous. Some specimens have the ambu- 

 lacra more prominent than others, and the avenues a little sunk. 

 The mouth varies in shape and in the depth of the notches. The 

 anus is rounder when young, and more angular in old specimens. 



History, — Knorr's old figures of this fossil are tolerably charac- 

 teristic, and it is generally believed he intended this species. 

 He refers also to Klein ; and in Leske's " Additamenta'' to tbat 

 author (1778), Knorr's figure is wretchedly copied, and made to 

 look like a many-lobed species.* The specimens were found with 

 acicular spines in connexion with them at Pfeffingen, in Basle, 

 from which locality Desmoulins quotes the species as one he had 

 not seen. 



Agassiz and Desor, in the Catalogue Raisonn^, refer to Desmarest 

 for the name. His short description, in the Diet, des Sc. Nat., 

 states that his specimen had no locality, but that it was probably 

 from beds older than the chalk, and that others very like it were 

 found in the Jura. Goldfuss, in 1826, gave an excellent figure of 

 it, under the name of E, lineatus, showing clearly the granules in 

 circles round the tubercles, and also the parallel rows of pores. He 

 has well expressed the general rough appearance of the species, 

 even better than in Agassiz's more complete figure in the Ech. 

 Suisses. In that work a smaller variety was figured, and called 

 by Agassiz E. psammophorus^ which he afterwards united with 

 the larger species ; and also the E. serialis, which he does not 

 appear to have regarded as a mere variety in his Catalogue Rai- 

 sonnd, 1846. In the meantime Phillips had, enumerated, without 

 a description, the variety germinans in the Geology of Yorkshire,f 

 which Prof M'Coy republished, in 1848, as E. diademata, from 

 the original locality. M. Cotteau's description and figures of his 

 E. multigranularis are good representations of the typical E. per- 

 latus ; and lastly, Dr. Wright has described a large conical variety 

 and a depressed one (the latter as E. serialis) from his own neigh- 

 bourhood in Gloucestershire. His description rightly includes a 

 synonymy of the several varieties, and this has been confirmed by 

 the late Prof E. Forbes, in the second edition of Morris's Catalogue, 

 1854. The var. serialis and that we here term Forhesii were not 

 included in that synonymy, but, in accordance with the Professor's 



* Unless indeed there is a general mistake in referring to that figure, which may very 

 probably be intended for the E. gyratus. See note on that species. 



t " His figure, a slight outline, is characteristic enough, but the avenues of pores are so 

 indicated that the pores might be supposed to be in single file" (Forbes). 



