162 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 25, 



My proposed general term — the Lower Palaeozoic division of the 

 " Primary System," including the Cambrian Series and the Silurian 

 Series — may at present serve our purpose, until our views become 

 better defined by better knowledge. There is not a single known 

 palaeozoic rock of Britain that I have not studied ; and this at least 

 I may assert, as the result of this study, that it is from the Cum- 

 brian and the Welsh mountains that we must construct our British 

 types : and the pheenomena of these mountains are the foundation 

 of everything I have offered in this paper in the way of classification 

 and nomenclature. 



Since the extension of the lower Silurian colour over the whole 

 Cambrian series by Sir R. I. Murchison, there has, I know, been a 

 general opinion, that I had made some great mistake in my estimate 

 of the palseontological characters of the Cambrian series ; that in 

 using the words Cambrian System, I had supposed that the Cam- 

 brian fossils formed an entirely distinct zoological group from the 

 Lower Silurian*. Now this I never once asserted; and, from the 

 first, I knew that the very contrary was the case ; and it was this 

 knowledge which made me many times in this room object to any 

 strict palaeontological use of the word system, when applied to Cam- 

 brian and Silurian rocks. Although my great Welsh series of rocks 

 and fossils was inaccessible to myself until my new museum was 

 opened for the reception of a vast, and till then unapproachable, col- 

 lection, yet I had in reserve a small series of specimens from Bodean, 

 Snowdon, Moel Hebog, Bala, Meifod, &c. ; and these, as well as my 

 field notes and sections, led me to assert, many times, during the dis- 

 cussions in this room, that the word system, as used by its author, 

 was not philosophically applied to Silurian rocks which had not, so 

 far as I could discover, either a good physical or palseontological base. 

 Turn, for example, to the Proceedings (May 1838, vol. ii. p. 679), 

 where, writing of the "Upper Cambrian System," I use the follow- 

 ing words : This system " commences with the fossiliferous beds of 

 Bala, includes all the higher portions of the Berwyns, and all the 

 slate-rocks of South Wales which are below the Silurian System.". . . 

 " Many of the fossils are identical in species with those of the lower 

 division of the Silurian System, nor have the true distinctive zoolo- 

 gical characters of the group been well ascertained." In the same 

 page I add as follows : " At the north end of the Berwyn chain it " 

 (the Tipper Cambrian System) " appears to pass by insensible grada- 



* This error regarding my own meaning, whenever 1 made use of the words 

 Cambrian System, originated, I doubt not, in the writings of my friend, after he 

 had detected his sectional mistakes, and began to change his own views respect- 

 ing the relations of his Silurian rocks to the great groups which he had placed 

 below them. Thus, when he tells me (Quart. Journ. Geol. Soc. 1847, vol. iii. p, 1 73) 

 that *' the recognition of a Cambrian System has been considered to be exclusively 

 dependent on the discovery in it of a peculiar type of life distinct from that for- 

 merly described as Silurian," he writes in direct contradiction to his own inter- 

 pretation of phaenomena made, along with myself, in the field (in 1834), and in 

 apparent contradiction to various passages of his great work ; and he now en- 

 deavours to saddle me with a technical meaning of the word system which I 

 never once made use of, and against which he had heard me enter ray protest long 

 before there was a word of controversy between us. 



