388 VEGETATION OF THE CARBONIFEROUS PERIOD 



From the very outset it must be borne in mind, that whatever light 

 future investigations of hitherto unexplored coal-fields may throw upon ' 

 this most difficult subject, we can never hope thereby to arrive at any 

 great amount of precision in determining the species of vegetable re- 

 mains, nor to ascertain the degree of value due to the presence or 

 absence of certain forms, such as the animal kingdom so conspicuously 

 affords. Still less can we expect that they will prove equally appre- 

 ciable indices of the climate and other physical features of that portion 

 of the surface of the globe upon which they once flourished. 



The great extent of the vegetable kingdom is hardly to be appre- 

 ciated except by the professed botanist ; and he must be an advanced 

 student who knows as much of its main features as he may acquire of 

 the animal creation during the course of an ordinary education. Every 

 one, for example, is familiar with the divisions of the class Animalia 

 into beasts, birds, fish, reptiles, shells, &c. ; but much study is required 

 to attain an equal amount of acquaintance with the parallel divisions of 

 plants into exogenous, endogenous, &c. The technical terms, too, 

 employed in the one case are, very many of them, universally intelli- 

 gible ; whilst the majority of those applied to the more conspicuous 

 organs of plants must be acquired by a special study. Lastly, the ex- 

 ternal organs of vegetables, and especially such as are generally avail- 

 able in the fossil state, are not the same guides to the affinity of the 

 objects themselves, to their habits, or to the nature of the area they 

 occupied, which the similarly conspicuous organs of animals are. Thus, 

 were fossil vegetables much more perfect than they are, the informa- 

 tion to be derived from their study will never hold a rank of equal 

 importance to the geologist with that afforded by animal remains. 



It is partly owing to these circumstances that the study has been 

 comparatively neglected ; partly also because a far more comprehensive 

 knowledge of the existing forms of plants is required to make any 

 progress in fossil botany, than of recent zoology to advance equally in 

 palaeontology ; for, whilst an acquaintance with a single class of ani- 

 mals (the shells for instance) enables the - student to understand and 

 distinguish whole formations, he cannot, without being somewhat con- 

 versant with all classes of living plants, appreciate the value of the most 

 perfect series of them in a fossil state. 



Turning from this discouraging view of fossil botany in general to 

 that of the particular formation to whose consideration the remainder 

 of these pages will be devoted, it is satisfactory to find that it presents 

 facilities for the investigation of its vegetable remains such as is afforded 

 by no other. This is mainly due to the vast accumulation of specimens, 

 and to many of them being presented under very different conditions in 

 the under-clay, in the shales, in nodules of ironstone, and in the sand- 



