Rocks of North Devon, ^c. 121 



they have a great unity of character *. To these views, so 

 clearly expressed, I fully subscribe. 



Upon the whole, there appears to me no adequate reason 

 for considering the Older Stratified Rocks of Devon otherwise 

 than as a portion of the transition system ; for the occurrence 

 of certain fossil plants in the Wollacomb and Marwood bed 

 of sandstone (subjacent to the Trilobite clayslate), even should 

 they really be found to bear analogy to some that are met with 

 in the coal-measures, does not seem sufficient to invalidate 

 this conclusion. It is much to be desired that the fossil plants 

 derived from the Marwood sandstone should undergo a ri- 

 gorous examination as to the different genera and species 

 of which they may consist, especially as the evidence hitherto 

 given in respect of them is in some degree conflictive f. It 

 may be remarked, however, of these sandstones, that among 

 them none of the fern tribe have been met with, whilst these 

 are of frequent occurrence among the Devon coal-measures. 

 That fossil plants occur also in the South of Ireland, among 

 the transition strata at Dunmore, in the county of Kerry, as 

 noticed by the late Mr. Alexander Nimmo, 1 have already 

 placed on record J ; and I have to express my regret that I 

 received that information subsequent to my visits to that part 

 of the island. It is very desirable that some competent geo- 



* Proceedings of the Geol. Society, vol. ii. No. 58, pp. 683, 684. May 

 1838. 



t Professor Lindley is stated to be of opinion that none of these plants 

 derived from the Marwood and, Wollacomb sandstones are similar to 

 those which are common to the Devon culm-measures : some resemble 

 f^iicoYUcated Le2ndodendra and others Sternbergia ? One specimen resembles 

 Calamitcs Voltzii of the terrain d'anthracite inferieur (Voltz). (Proceedings 

 of Geol. Society. Prof. Sedgwick and Mr. Murchison, in vol. ii. No. 51. 

 p. 559.) But such of the plants occurring in the Devon culm-measures 

 near Bideford, &c. as were determinable, had been identified by Professor 

 Lindicy with species characteristic of the true coal-measures. {Ibid, the 

 President's addresses in No. 39, p. 163, and No. 49, p. 491. And Prof. 

 Sedgwick and Mr. Murchison in No. 51, pp. 561, 562.) 



It has, however, been also stated that some of the plants of the Wolla- 

 comb sandstones are supposed to be true carboniferous plants, while all 

 the plants in the culm-measures are described as identical in species with 

 plants of the carboniferous series. {Ibid. Prof. Sedgwick in No. 58. p. 681. 

 May 1838.) 



And Prof Sedgwick and Mr. Murchison repeat that some of the plants 

 from the Marwood, &c. sandstones are considered by the Rev. David Wil- 

 liams and Mr. De la Beche, on the authority of Dr. Lindley, as undistin- 

 guishable from plants of tlie carboniferous system. (Lon. and Edin. Phil. 

 Mag., vol.xiv. p. 243. April 1839.) 



See also Mr. De la Beche's own statement, in reference to both these 

 subjects, in the Report on Cornwall, &c., pp. 50 and 126 j the authority 

 of Prof. Lindley being in both cases referred to. 

 X Geol. Trans., vol. v. second series. Memoir on the S. of Ireland, §. 13. 



