724 



THE WONDERS OF GEOLOGY. 



Lect. VII. 



inhabiting woods and bogs ; their leaves are simple and im- 

 bricated, that is, lie over each other like scales. Most of 

 them trail on the ground, but a few species are erect ; the 

 tropical forms, which are the largest, do not exceed three 

 feet in height. But notwithstanding this disparity in size, 

 M. Brongniart has shown that the Lepidodendra must be 

 regarded as gigantic plants of this family. They were, 

 in fact, arborescent Lycopodiaceae, comparable in size to 

 the largest pines, and formed extensive forests during the 

 carboniferous epoch, beneath whose shade flourished the 

 lesser ferns and associated plants. 



The fruit of the living Club-mosses is an oval or cy- 

 lindrical cone, which in some species forms an imbricated 

 spike at the extremity of the branches ; and there are 

 numerous fossil fruits of this kind collocated with the stems 

 and leaves of the Lepidodendra, and in some instances 

 attached to the branches ; they have received the name of 

 Lejndostrobi, or scaly-cones.* 



A beautiful example of a fossil 

 Lycopodium, from a tertiary for- 

 mation in the Tyrol {Lign. 164), 

 closely resembles the recent club- 

 mosses. 



39. Coniferous Trees and 

 Plants. — It was formerly sup- 

 posed that no vestiges of conife- 

 rous plants and trees, which occur 

 so abundantly in the secondary 

 lign. 165.— Transverse section of formations, were present in the 



a portion of the stem of a recent COftl but Mr. Witham, by mi- 

 Pine {Pinus slrobus), highly ■ # # ' J 



magnified. croscopical examination, ascer- 



a. 6, Portions of concentric ta i nec l t ] iat treeg f this type 

 annu al layers. . . , ■ 



constituted no inconsiderable por- 

 tion of the flora of the carboniferous epoch ; and remains 

 * Medals of Creation, p. 149, Lign. 31. 



