THEIR ANCIENT LINEAGE 



development of the vegetable kingdom. The fossil 

 remains of plants and animals imbedded in the rocks 

 of the different geological epochs of the world's his- 

 tory tell the story of the progressive changes that 

 have taken place during the earth's history, from its 

 youth and adolescence to its present age. Indeed 

 this progressive development of organic life through 

 successive geological periods is the theory on which 

 the modern teaching of the science of natural history 

 is based, and it must be confessed that it goes far 

 toward rendering intelligible natural phenomena as 

 they exist to-day. 



Trees by no means represent the oldest type of life- 

 forms in the history of the vegetable kingdom; on 

 the contrary, they are fairly modern. Geologists 

 tell us that in the earliest phases of the world's his- 

 tory of which organic remains exist, the vegetable 

 kingdom was represented by simple, aquatic, or semi- 

 aquatic plants, and the animal kingdom by sponges, 

 worms, centipedes, and spiders. In succeeding ages 

 land plants were developed. During the period 

 represented by our coal measures (the Carboniferous 

 period) and the lengthy epoch preceding it, the whole 

 earth became more or less forest-clad with a low 

 type of vegetation mostly allied to our Ferns, Horse- 

 tails, Lycopods, and ancestral forms of the Cycad 

 and Ginkgo families. 



9 



