391 



II. On the occurrence of stems of fossil plants in vertical positions 

 in the sandstone of the hferior oolite of the Cleveland Bills. 



After a short illustration of the nature and arrangement of the dif- 

 ferent members of the oolitic series in the north of Yorkshire, for fuller 

 details of which he refers to Phillips's Geology of Yorkshire, and 

 having mentioned a vast number of new species of fossils, collected on 

 the coast of Scarborough by Messrs. Bean, Dunn, and Williamson, the 

 author proceeds to give a particular account of a discovery recently 

 made by himself of the stems of Equisetum columnare, arranged in 

 vertical positions in the escarpment of the lower carboniferous sand- 

 stone of the oolite at Carlton Bank, near Stokesley, Yorkshire. A 

 similar phenomenon was first made known by Messrs. Young and 

 Bird, and subsequently by Mr. Phillips, as respected a portion of the 

 coast between Scarborough and Whitby ; but owing to the limited 

 field in which it was observed, nearly all geologists continued to be 

 of opinion that the plants thus found had been accidentally collocated 

 by drifts and currents of water. The recent discovery of these stems in 

 an upright position in the same stratum, far in the interior, and 

 40 miles distant from that point of the coast where they were first 

 noticed, induced the author of this memoir to infer that this peculiar 

 arrangement, at points so distant from each other could not have 

 been fortuitously produced, and that therefore these plants like those 

 of the dirt bed in Portland*, are still in the place of their growth. 

 The author had observed the vertical stems in the Yorkshire coast in 

 the year 1826; and in returning to Scarborough last summer, after 

 making the discovery at Carlton Bank, he was confirmed in the 

 conclusion to which he had arrived, by learning from Messrs. Wil- 

 liamson and Bean that all the Equiseta found by them in the lower 

 sandstone and shale, since his first visit, were invariably in vertical 

 positions. He further ascertained that the only fossil shell which had 

 been detected in the associated strata of the lower sandstone and 

 coal, was a fresh water bivalve ; and the fine lamination of the beds 

 indicated that they must have been formed in a tranquil manner. In 

 the overlying formations, on the contrary, all the fossil shells are of 

 marine origin ; and although in one of them vegetable matter and coal 

 are also found, yet the stems of the Equisetum are never vertically 

 arranged as in the lower sandstone, but are confusedly mixed up with 

 other vegetable detritus. 



From these data the author concludes, that during the formation of 

 the sandy lower oolite of Yorkshire, the dark, shale beds in which the 

 Equiseta still seem to be rooted, were exposed to the atmosphere — 

 that these stems have never been detached from the place of their 

 growth, but have been sustained in their original positions, having 

 been first gradually silted up, and then buried under the accumu- 

 lations of an estuary, the matter in which having consolidated round 

 them, has retained the forms of their lower parts ; — that afterwards 

 these vegetable and carbonaceous strata were covered by a sea in 



* See the abstract of Dr. Buckland and Mr. De la Beche's paper en 

 Weymouth, p. 219. 



