THE NEW EVOLUTION '^f 



ing to them bits of their skin-like covering. In the 

 mountains of Tennessee I have seen somewhat similar 

 sea beaches, also with shells and other marine objects, 

 turned to stone; but it has been a very long time since 

 this region was part of any sea coast. 



When animals die and after death lie on the surface 

 of the ground they gradually decay and their bones 

 become scattered and broken up. In order to be pre- 

 served they must be buried. 



In the frozen ground of northern Siberia the woolly 

 arctic elephant or mammoth and the woolly rhinoc- 

 eros are occasionally found with the skin, hair and 

 wool and even the flesh preserved. The flesh can 

 still be eaten although it has been in cold storage for 

 something like fifteen thousand years. From the 

 plant remains found in the stomachs and in the 

 mouths of these frozen mammoths we even know 

 what they fed upon. Their food was furnished by 

 the same plants that now flourish in the region. 



But it is only very seldom that the flesh, skin or 

 hair of the animals of the distant past have been dis- 

 covered. As a rule only the skeleton is preserved. 

 Yet imprints of birds' feathers have been found in 

 several places, and indeed the first trace of the most 

 ancient bird we know, the so-called Arcbaopferyx, was 

 the imprint of a feather. 



The most spectacular of all the regions where fossils 

 have been found in North America is Rancho la Brea, 

 within the city limits of Los Angeles, California. 

 Here over a vast period of time asphalt has been accu- 

 mulating from escaping oil. In this sticky asphalt 



