.Geological Society. 225 



duce. Erica vagans terminates its northern range on the serpentine 

 of the Lizard ; Draba aizoides, in Gower. 



The author then proposed to consider the vegetation which is pro- 

 duced by the different strata, commencing with the eastern side of 

 the kingdom, or with the most recent deposits. 



The diluvial soil of the Fens, which is composed of decayed vege- 

 tables resting on clay, is, when left to nature, soon covered with 

 grasses, to the exclusion of every other plant. Scarcely a single rare 

 species is to be found on it. The water in such soils, on the con- 

 trary, abounds in rarities. Stratiotes aloides, Arundo calamagrostis, 

 Teucrium Scordium, Lactuca Scariola, Senecio paludosus, &c. &c. are 

 of this number. The author remarked, that the first of these species, 

 though wild in Berkshire, had not been observed to flower there. 

 Arundo calamagrostis he regards as peculiarly a Fen plant with us, 

 and that the localities assigned to it elsewhere belong to A. epigejos. 

 This locality appears to be on its most southern limit. The most re- 

 markable feature of Fen vegetation is the luxuriance and quantity of 

 Cruciferae. 



Whatever phenomena geologists may discover to induce them to 

 regard the Bury sand as the same with that of Bagshot-heath, the 

 author remarks that their vegetable productions do not correspond ; 

 and though he does not assert that we ought to find a similar vegeta- 

 tion on strata of the like nature, yet it so frequently occurs that the 

 rarer plants correspond where strata are alike, that he regards such 

 differences as worth noticing. 



The rare plants of the Bury sand are peculiar to itself, while the 

 Bagshot sand is remarkably deficient in uncommon species j the only 

 one of notoriety, he has remarked, being Agrostis setacea, which is 

 abundant, and which may be traced upon the sands and gravels of 

 the plastic clay, through Dorsetshire, Hampshire, Surrey, and even 

 to the Commons in the neighbourhood of London, where its range 

 terminates. 



GEOLOGICAL SOCIETY. 



Feb. 1. — The reading of Professor Sedgwick and Mr. Murchison's 

 paper, begun at the last meeting, was concluded. 



This paper consists of three divisions : 1st. A brief outline of the 

 general structure of the Isle of Arran. 2d. An account of the section 

 on the N.E. coast of the island. 3d. Concluding remarks explanatory 

 of the probable causes, and geological epochs of the several phe- 

 nomena. In the 1st division, the authors, considering that the sub- 

 ject has been amply elucidated by Jameson, MacCulloch, and Hen- 

 drick, confine themselves to such details as are necessary to make 

 their subsequent description intelligible. In the 2d part, the strata 

 on the N.E. coast are described in great detail, for the purpose of 

 comparison with the corresponding members of the English Series $ 

 from whence it appears, that a succession of formations, analogous to 

 the old red sandstone, carboniferous series, and new red sandstone, 

 are exhibited twice over, in an anticlinal section. 



New Series. Vol. 3. No. 15. March 1828. 2 G The 



