491 



years the Society has been anxiously desiring more accurate infor- 

 mation ; 1 allude to the true stratigraphical position of certain 

 shales near Bideford in North Devon, containing fossil plants of the 

 same species as those which are found abundantly in the coal. I may 

 first remind you that a discussion had pi*eviously arisen respecting 

 the alleged discovery by Mr. Weaver of anthracite, with the usual 

 carboniferous plants, in the greywacke or transition rocks of Ire- 

 land*. Notwithstanding the value justly attached to the opinion of 

 so experienced and long-practise d an observer, your Council hesi- 

 tated to print his statement, and requested him to reexamine the 

 ground. At the same time Mr. Griffiths, to whom we are looking 

 for the publication of a Geological Map of Ireland, had come to a 

 different conclusion, and Mr. Weaver having been induced to repeat 

 his observations, became convinced that he was in error, and has 

 since studiously availed himself of every opportunity of announcing 

 this change in his views. 



You are aware that as yet in the British islands, scarcely any vege- 

 table impressions have been met with in rocks more ancient than the 

 carboniferous strata above the old red sandstone, so that we know not 

 what species of plants belong to the greywacke or transition group. We 

 can only presume from analogy that since the shells, corals, and other 

 organic remains of that ancient group differ from those found above 

 the old red sandstone, the plants also, if ever discovered, will differ 

 as greatly. Considerable surprise was therefore excited when, 

 during the Presidentship of my predecessor in this chair, a letter 

 was read, addressed to him from Mr. De la Beche, stating that he 

 had found, near Bideford in North Devon, many well known coal 

 plants in the lower greywacke, or far down in the transition seriesf. 

 Such of the plants as were determinable had been identified by 

 Professor Lindley with species characteristic of the true coal 

 measures, and which had never been found elsewhere below the 

 coal. The anomaly, therefore, in the supposed position of these 

 fossils was so great, that between the ordinary geological site of 

 such remains, and that in which they were here inferred to present 

 themselves, there would be interposed if the series were complete 

 the whole of the old red sandstone, and at least the two upper forma- 



* Proceedings Geol. Soc, vol. i. p. 231. 

 t Proceedings Geol. Soc, vol. ii. p. 106. 

 VOL. II. 2 N 



