422 Notices and Extracts from the Minutes of the Geological Society. 



of sandstone slate 7 feet thick, contains bones and teeth of crocodiles and of 

 some unknown animals, fishes, turtles, birds, carbonized wood, vegetables, 

 and casts of univalves and bivalves. 



" 4. A coarse aggregate of quartz, limestone, and sandstone pebbles, and 

 immense quantities of comminuted bones and teeth of fishes, the whole loosely 

 held together by a coarse grit. It varies in thickness from 3 to 6 feet. 



" The vegetable fossils which form the immediate object of our investigation, 

 are almost entirely confined to Nos. 2. and 3. ; and in both of these beds are 

 exceedingly abundant." 



Partial subterranean floras, such as the present, will enable us to ascertain 

 what different orders of vegetables have progressively clothed the successive 

 crusts of our planet, and to identify strata by their fossil vegetation, equally as 

 well as we now do by their zoological contents. 



In the present instance we arrive at least at one interesting fact, in regard 

 to that numerous fossil order the Ferns, which were before onlv known to 

 range from their principal habitat the carboniferous series of rocks to the 

 oolitic formation, in which they occur in the Stonesfield slate. We now find 

 them in the ferruginous sandstone ; but as yet they have not been detected 

 in the chalk or in the beds above that great division. 



The absence of the organs of fructification in fossil plants, the imperfect 

 state of the plants themselves, and their anomalous character when compared 

 •with their recent congeners, have tended, as yet, to retard their study and 

 "arrangement. A system, however, founded on the few external characters 

 they present, has been formed by Messrs. Schlotheim, Sternberg, and Adol- 

 phus Brongniart ; but chiefly arranged and consolidated by the latter. This 

 system, for the convenience of identification and comparison, it may be 

 useful for us to adopt. 



Plate XLV. figs. 1. 2. and 3. represent different portions of a trunk or 

 caudex, scored on the surface, somewhat after the manner of those of the 

 genera Zamia and Cycas, but altogether differing from them, or any other 

 known family, in inclosing an internal body marked likewise on its surface ; 

 and that very differently so from the external covering. See PI. XLV. fig. 1., 

 PI. XLVI. fig. 8., and Pl.XLVII. fig. 4. a. Between these is apparently inter- 

 posed the cellular substance, represented moderately magnified PI. XLVII. 

 fig. 4. d. The markings on the inner surface sometimes appear decidedly 

 imbricated ; which has been carefully represented PI. XLVII. fig. 4. c. A 

 cicatrix, possibly that of a branch, has been drawn PI. XLVII. fig. 4. h. This 

 appearance, however, of the setting off" of a branch from the inner surfiace, 

 may be deceptive ; and here the trunk of a Dracaena Draco, existing in 



