142 The Bible of Nature 



also by palimpsests, one record on the top of 

 another. 



We cannot wonder at "the imperfection of the 

 geological record," when we remember how young 

 palaeontology is, how young, for that matter, man 

 is his whole history but a tick of the geological 

 clock; how many areas are still unexplored; how 

 much ground being covered by sea must re- 

 main unknown. We cannot wonder that the ma- 

 terials of the history are scrappy when we under- 

 stand that only hard organisms or hard parts are 

 likely to be preserved, that only certain kinds of 

 rocks are suitable tombs, and that many rocks have 

 been unmade and remade many times over. As 

 we walk along the shore and study the jetsam, we 

 see how quickly many of the sea's memoranda 

 are obliterated. The wonder really b that the 

 record is as complete as it is, that from " the strange 

 graveyards of the buried past" we can learn so 

 much about the life that once was. 



It is impossible to read even a little about the 

 study of fossils without a thrill of admiration for 

 the patience and insight of the biological archae- 

 ologist. He tells us of fossil jellyfishes and of the 

 young stages of Graptolites; he makes from frag- 

 mentary specimens a vivid reconstruction of a prim- 

 itive Vertebrate not much over an inch in length; 

 he makes the great dragons of the prime disport 

 themselves before us; he counts the cuttlefish shells 



