EXTINCT ANIMALS 



Trilobites and Lingula by as long a period as 

 these latter precede the animals living to-day. 

 Apparently the soft-bodied animals which pre- 

 ceded the Cambrian fossils have not left any 

 remains in the rocks below the Cambrian or their 

 remains have been destroyed by chemical and 



Fig. 202. — The Desert Scorpion (Buthus australis). Drawn 

 from a living specimen in the author's laboratory. 



structural change in those most ancient deposits. 

 The Scorpion itself (Fig. 202) is a very ancient 

 and important animal which so far impressed 

 the imagination of even the earliest civilized 

 men, that they named one of the constellations 

 after it. Some hundreds of distinct species of 

 scorpions are known as living at the present day 



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