﻿STREPT01UIYNCHUS. 



79 



that the shell had been found in the Devonian rocks of Gerolstein in the Eifel, as well as 

 in the Carboniferous limestone of Bolland, in Yorkshire ; while 0. pecten he considers to 

 be a distinct species. About the same period Sowerby published a description of the 

 British Devonian form, under the designation of Spirifera (?) crenistria (Phillips), and 

 adds, that his own S/>. reticulata (' Encyolop. Metrop.,' art. Geology) is a synonym. 



In 1S40 M. dc Verneuil described Orthis umbraculum, from Fcrques, and considered 

 Phillips's Sp. crenistria a synonym. In 1841 the same author again, in the 'Trans, of 

 the Geo!. Soc. of London/ made use of the term umbraculum for the Devonian as well as 

 for the Carboniferous shell, adding, at the same time, that Strophomena pileopsis, Rafinesque, 

 must be numbered among the synonyms of umbraculum. In 1845 (at p. 188 of vol. ii, 

 of the ' Geology of Russia') M. de Verneuil recalls his former statements, and is of 

 opinion that the Carboniferous and Devonian shells may be distinct, and he therefore 

 adopts both Schlotheim's and Phillips's denomination, but adds, " Nevertheless, we must 

 confess that it is not always an easy matter to distinguish these two species, especially 

 when one has before one's eyes only figures and descriptions." 



In 1841, while describing the fossils of Cornwall, Devon, and West Somerset, Pro- 

 fessor Phillips applied the term Spirifer (?) crenistria to the Devonian shell, but interro- 

 gated at the same time whether it might not be the same as the Orthis umbraculum (?) of 

 Von Euch. 



In 1843, Portlock makes use of the name Orthis umbraculum for the Carboniferous 

 species ; and in the same year Professor L. de Koninck likewise adopts the term um- 

 braculum for the Carboniferous shell; but at p. 655 of the Supplement to his ' Description 

 des Animaux Eossiles de la Belgique/ published in 1851, he recalls his former statement, 

 and expresses the opinion that 0. crenistria, Phillips, is distinct from 0. umbraculum of 

 the Devonian period, adding at the same time that the two species are very well dis- 

 tinguished by the shape of their areas, and by that of their ornaments. 



In 1848, in his Index Palaeontologicus, Bronn considers 0. umbraculum, 0. crenistria, 

 and 0. pecten (Dalman) to be distinct species, with the following synonyma — 



1. Orthis umbraculum, Buck = An. pecten, Linn. Syst., xiii, 1152 = Stroph. pi/eopsis, Raf. 



2. — crenistria, Phil. — Sp. senilis, Phil — Orthis umbraculum, var. senilis, De Kon = 1 Sp. reticu- 



lata, J. Sow., Geol. Trans. 



3. — pecten, Dalman (not A. pecten, Lin.) = An. pecten, Wahlb., Schlotheitn, &c. 



From the above it is evident that Bronn was not well acquainted with the An. 

 pecten of Linnaeus, which is the same as that subsequently described and figured by 

 Dalman. His synonyma are also, in other respects, defective. 



In 1853, Professor Schnur makes use of the term Orthis umbraculum for the Devonian 

 form. 



In 1854, at p. 137 of his 'Catalogue of British Fossils/ Professor Morris adopts — 



