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in the opinion of Professor Sollas he is entitled to 

 be considered the 'Father and Founder' of Geology (33). 



It was by slow degrees that the early observers 

 freed themselves from the obsession that the remains 

 of animals and plants in the earth's crust bear witness 

 to a Universal Deluge and are all identical with 

 existing species. The possibility that some of the 

 fossil plants in English strata might be more clearly 

 related to forms now met with in Avarmer regions 

 was gradually realised. The publication of the 

 Origin of Species stimulated palaeontological 

 research, and botanists as well as zoologists turned 

 to the investigation of extinct genera in search of 

 proofs of the doctrine of evolution. 



The common occurrence of petrified wood in 

 rocks of diflferent ages is well known. Fossil stems 

 are occasionally found in their natural position of 

 gi-owth, the structural details being rendered perma- 

 nent by the deposition of siliceous or calcareous 

 material from water drawn by capillarity into the 

 dead but still sound tissues. Petrified wood from 

 Upper Jurassic beds is abundant in the Island of 

 Purbeck ; an unusually long piece of stem may be 

 seen in the small town of Portland fixed to the wall 

 of a house. Some of these stems have been referred 

 by an American author to the Araucarian family of 

 Conifers, but the structure is as a rule hardly well 

 enough preserved to afibrd satisfactory evidence for 



