Excavating for fossils at La Brea. Many white weathered fragments of bone 

 tered over the surface. Oil-wells in the distance 



larger and more numerous and formed a death-trap of terrible efficiency for 

 the numerous animals that inhabited the valleys and plains of that region. 

 This was in the Pleistocene Period, during the Glacial Epoch, when much of 

 the northern part of the continent was buried under great fields of ice. 

 Southern California, far below the southern limits of glaciation had probably 

 a less arid climate than now, and a very large and varied animal population, 

 mostly of extinct species and some of them very widely different from the 

 living animals of the region. 



Excavations for road asphalt in this formation were commenced in 1874 

 by Major Hancock, the owner of the ranch. The material was melted down 

 to free it from impurities and shipped in barrels to San Francisco and else- 

 where. The work was not continued as the cost of purifying the product 

 was too high for it to find a profitable market at that time. It served to 

 call attention to the fact that the asphalt contained numerous bones or 

 fragments of bones, and when examined by scientists it appeared that these 

 were not modern bones but belonged to extinct animals. Prospecting for 

 fossils soon showed that around the little oil springs or where springs had 

 formerly come up, there were pipes or chimneys of soft asphalt, which were 

 veritable ossuaries, packed full of the bones of these extinct animals, mostly 

 in marvelous preservation. The excavations of the local scientific societies 

 and the more extensive work carried on by the University of California have 

 yielded many hundreds of skulls and tens of thousands of skeleton bones, of 

 a great variety of animals large and small. The bones are impregnated 

 with asphalt, otherwise little altered ; but flesh and hide, horns and hoofs 



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