HORTON — GEOLOGY OF THE STONESFIELD SLATE. 



253 



plete list of the fossils of tliese beds has not yet been formed, pro- 

 bably because there is no complete collection of them in existence. 

 Perhaps the Oxford Geological Museum contains the finest series, 

 chiefly collected by the late Dr. BucMand, who paid frequent visits 

 to this village, and with whose memory the formation under review, 

 rendered classic by his labours and fame, will ever be associated. 



Let us now proceed to glance at these products of the slate-pits, 

 and it will be seen that they comprise a marvellous variety of 

 organic remains ; for, besides plants, insects, reptiles, and mammalia, 

 indicative of dry land, the Crustacea, shells, and predaceous shark- 

 like fishes of the Oolitic ocean are likemse represented in the 

 catalogue. 



We begin with plants, and notice one marine form, a branching 

 facoid, or sea-weed, Halymenites ramulosus. Among the ferns that 

 once flourished on that ancient shore, whose dark impressions are 

 presented in beautiful relief on the light grey of the slate, we find 

 the dehcate fronds of Sphenopteris (S. cysteoides) and Hymeno- 

 phyllites (H. macropliyllct) , together with the broad-leaved tribe 

 Tasniopteris, one species of which (T. vittata) is identical with the 

 form found in the carbonaceous shale of the Lower Oolite on the 

 Yorkshire coast, in the vicinity of Scarborough. The beautiful 

 Cycadaceee, of which the Zamia of New Holland gives an existing 

 example, are represented by such forms as Palseozamia (F. ijedinata, 

 P. taxina), Zamites (Z. Imiceolatiis) , and Pterophyllum (P. comjjtum, 

 P. minus). The three last*named species occur likewise in the Scar- 

 borough oolite. There is also a singular reed-like leaf, as yet unde- 

 scribed, about twelve inches in length by one in breadth, destitute of 

 a mid-rib, and with nervures parallel with its edges. The small 

 extreme branches of coniferous plants are among the frequent fossils 

 of the slate. One kind possesses afiinities with the yew (Taxites), 

 but most of them are more allied to the cypress, and have received 

 the name of Thaytes (Thuytes cupressiformis) , with three other 

 species. Of the fruits of these coniferas there are several varieties, 

 one kind in shape and size not unlike the berry of the yew, some of 

 its more perfect examples still retaining their outer integument, or 

 husk. 



Examples of another species are termed by the quarrymen " plum- 

 stones," to which, in truth, they possess a resemblance. There is also 

 a fine Zamioid fruit, with the scales attached to the axis (BucMandia 

 squamosa) , and others that appear referable to large pine-like trees ; 

 these at present receive the merely provisional title of Carpolithes. 

 Besides these ferns and coniferous plants, there is likewise a small 

 one, whose delicate yet distinct impressions are apparently very much 

 akin to those of the moss family. N'either the roots nor stems of any 

 of these plants have been found at Stonesfield ; from this circumstance, 

 and that of their occuring as detached leaves and twigs, we may reason- 

 ably infer that the place of their interment was not the spot on which 

 they grew, but that they were drifted from some shore probably 

 lying at no great distance. 



