4 GEOLOGICAL MEMOIRS. 



great number of Crinoidal joints of most peculiar form and a well- 

 preserved new species of Terehratula, allied to Terebratula Livonica, 

 V. Buch, all changed into oxide of iron, which has, without doubt, 

 been formed from iron-pyrites. 



The fossils communicated by Prof. Krauss, although few in num- 

 ber, comprise three of the most important that are recognized in both 

 hemispheres as typical forms of the Lowest Division of the Rhenish 

 System. Tentaculites annulatus occurs both in this and in the Silu- 

 rian System. The new species of Terehratida is as yet peculiar to 

 the Cape, and of no use for the determination of the age of these 

 rocks. With regard to the species quoted by Murchison, D' Archiac, 

 and De Verneuil — Nucula Smithii is peculiar to the Cape ; Homalo- 

 notus Herschelii is as yet known in Europe only in the Spirifer-sand- 

 stone ; Homalonotus crassicauda { = H. Knightii, Keen.) occurs in 

 the Spirifer-sandstone and the uppermost Silurian (Ludlow) beds ; 

 Bellerophon acutus is found in England in the Caradoc sandstone, but 

 also, and not unfrequently, in our Spirifer-sandstone ; Conularia quadri- 

 sidcata included at the time the list was made a whole series of species 

 from different beds, nor can it serve for the determination of the system 

 before it is ascertained to which species the Cape specimen really 

 belongs ; Cucullcea ovata in all probability is not a well-determined 

 fossil ; and there remain as decidedly Silurian fossils only Calymene 

 Blumenbachii and C. Tristani. C. Blumenbachii has been quoted 

 by different authors too hastily as occurring in the Nassau Spirifer- 

 sandstone ; careful investigations tend to prove that imperfect speci- 

 mens of the head of Phacops laciniatus have been referred to this 

 species. Other Rhenish species of Phacops also have been con- 

 founded with C Tristani ; nor does the genus Calymene occur any- 

 where in the Rhenish System. 



These two forms, therefore, if Murchison' s determination be cor- 

 rect, would represent some Silurian rock. The rest of the fossils, 

 however, afford no evidence in support of this, but, on the contrary, 

 the three typical fossils of the Rhenish System, that are above re- 

 ferred to, show, without doubt, that these palaeozoic beds of the 

 Cape for the most part belong to the Spirifer-sandstone of the 

 Rhenish System. [T. R. J.] 



On Limestones in the Gneiss and Slate q/' Norway. 

 By Th. Scheerer, of Freiburg. 



[Zeitschrift der deutsch. geol. Gesellschaft. 1852, 4 Band, 1 Heft, p. 31-46.] 



The interesting results which Prof. Delesse has arrived at by geo- 

 gnostical and mineralogical examinations of the crystalline limestones 

 in the gneiss of Vosges* are an inducement for us to institute a com- 

 parison of these with analogous phsenomena in other countries. To 

 draw such a parallel in the case of the limestones of Norway is to me 

 the more interesting and important, as it is the fulfilment of a wish 

 expressed by M. Delesse in a letter to myself. 



* See Annales des Mines, tome xx. p. 141, &c. 



