XX PERMIAN FOSSILS. 



Permian from the Carboniferous rocks, as a system ; while the occurrence of the so- 

 called Limulus oculatus in the cupreous grits of Perm, and of such interesting forms 

 as Limulus anthrax, L. rotundatus, and other probably congeneric species, in the coal 

 field of Coal-brook Dale,^ links the two systems in close proximity to each other. 

 The Entomostracous Crustaceans have evidently abounded during the Permian epoch ; 

 as not only the Pelagic deposit (the Shell-limestone), but the apparently littoral or 

 shallow-water member (the crystalline) contain them, especially the latter, in profusion. 

 Mr. T. Rupert Jones has ascertained that some of these minute organisms are identical 

 with Carboniferoas species. Probably some of them will be found in the Permian 

 rocks of Germany; as Professor Naumann states, that the Mergerl-schiefer near 

 Oschatz is loaded with Cypris .• this reminds me of their prodigious abundance in the 

 limestone near Byers's Quarry, where they give the surface of the slabs quite a 

 granulated aspect. A species of Cythere occurs in one of my specimens of fossiliferous 

 limestone collected at Konitz. 



MoHusca. — Commencing with the lowest class of this extensive sub-kingdom, it 

 may be stated, that the Permian epoch was rather copiously provided with pallio- 

 branchiate forms. Twenty-three species belonging to ten genera are recorded 

 in the present work, to which may be added about fourteen more species, which have 

 been found in Russia. Germany and England have been represented by nearly the 

 same palliobranchiate fauna during the Permian epoch ; as most of the species, {Pro- 

 ductus Leplayi, and one or two more being the exceptions,) have been found in both 

 countries. Some species, as Trigonotreta alata, Camarophoria ScJdotheimi, Epithyris 

 elongata, U. svffiata, Cleiothyris pectinifera, have had their geographical range extended 

 to the North-eastern regions of European Russia, where they are associated with species 

 hitherto unnoticed in England and Germany ; namely, Chonetes sarcinulata, Strophalosia 

 Cancrini, S. horrescens, S. Wanyenheimi, and an un-named species of OrtJds collected by 

 Count Keyserling in Petschora-land. The genus Strophalosia, which is well represented 

 in the Permian rocks of Germany and England, is also very characteristic of those in 

 Russia ; but it would appear, that none of the species abundant in the former countries 

 have yet been met with in the latter one : there is^ however, a striking similarity between 

 their respective species ; for example, Strophalosia Morrisiana, and S. Cancrini,— 

 Strophalosia Wangenheimi, and S. Goldfussi. Of the family Strophomenida, the Permian 

 system appears to possess but one form, Chonetes sarcinulata (vide 'Geol. Russ.,' 

 vol. ii, p. 244), belonging to earlier rocks : this one, however, is of considerable 

 importance ; inasmuch as its occurring in all the divisions of the Protozoic period, 

 inseparably connects the Permian system with the earliest division of organic time. 

 The singular genus Streptorhynchus, which does not appear to reach further back than 

 the Carboniferous period, was represented during the Permian by a single species 



1 The Coal-"brook Dale Xiphosurians in the collection of Mr. J. Prestwich will afford a rich treat to the 

 Palseocrustaceologist. 



