Fossil Botany. 123 



parts of fructification of the ferns, the resinous secretions of 

 pine, and even the pollen of some coniferous plants, have been 

 found in good preservation. But vegetables occur not in such 

 conditions only, but in beds of great extent, consisting wholly 

 of plants transformed by the process which vegetable matter 

 undergoes, when under great pressure, and excluded from the 

 air, into masses of lignite and coal. " There are stages in this 

 process, when the form and structure of the plants can be dis- 

 tinguished, and a gradual transition may be traced from the 

 peat and submerged forests of modern periods, in which 

 leaves, fruits, and trunks of recent species are found, to those 

 accumulations of the ancient Flora, whose vegetable origin the 

 eye of science can alone detect." 



As fragments of the stem, or branch, or a single leaf, may 

 be the only vestiges of a fossil plant, some knowledge of the 

 internal structure which characterizes the principal divisions 

 of the vegetable kingdom, is obviously necessary. Here we 

 see one of the advantages of the Natural method. Were there 

 no other way of arranging plants, except that depending on the 

 construction of their flowers, the classification of fossil plants 

 would be impossible. By referring to our articles on the 

 Natural System, and on Vegetable Physiology, and to the 

 engravings in the article on the latter subject in the present 

 number, the following remarks on the mode of investigation of 

 fossil plants will be readily understood. 



Messrs. Lindley and Hutton, the distinguished authors of 

 the British Fossil Flora, remark, that a few isolated, and often 

 very imperfect data, exclusively afforded by the remains of the 

 organs of vegetation, are the sole guide to the class, order, or 

 genus of the fossil plants which are to be examined, and 

 hence only a general idea can be obtained of the nature of the 

 original. Their suggestions for the guidance of the student, in 

 his investigations, form the basis of the following directions for 

 the investigation of vegetable remains. If the wood in a trans- 

 verse section of the stem be disposed in concentric circles, (see 

 Veg. Phys., Fig. 11,) it belonged to an Exogen. If, on the 

 contrary, the wood appears irregularly deposited in spots, 

 (Fig. 9, a.) then the plant was an Endogen. If a transverse 

 section show remains of sinuous, unconnected, layers, like arcs 



