148 Biology in America 



of bones, great and small, saber-toothed tigers and giant 

 wolves, imperial elephants, camels, bison, horses and ground 

 sloths mingling their remains with those of mice, rabbits and 

 squirrels. Many of these bones are those of modern animals, 

 but a large number represent extinct forms. Of bird re- 

 mains the most striking are those of the giant condor, but 

 even more interesting are those of a peacock, an immigrant 

 from Asia, and unknown elsewhere in America. 



The frontispiece to Scott 's beautiful work on the mammals 

 of the western hemisphere is a drawing by Horsfall repre- 

 senting one of these tar pools of southern California in Pleis- 

 tocene time, which is of fascinating interest, especially to 

 one who has seen these wonderful collections of prehistoric, 



EXCAVATION OF A TAR PIT AT RANCHO LA BREA NEAR Los ANGELES, 

 CALIFORNIA. Original. 



mingled with modern life. Mixed in the tar at the edge of 

 the pool lies the carcass of a giant elephant, over which a 

 giant wolf and a saber-toothed tiger are quarrelling for pos- 

 session, while another wolf caught in the tar nearby snarls 

 defiance at the others.- In the background, perched on a 

 dead tree, or soaring overhead, are expectant condors, wait- 

 ing to feast upon vanquished and victor, when they like 

 their prey shall have fallen victims to the relentless tar, 

 while on the shore are the bleaching bones of some former 

 visitant to the fateful pool. And thus may we picture to 

 ourselves the tragic fate of creatures whose remains have 

 come down to us today to tell the story of the life that was. 

 Here too are found the bones of camels which once inhab- 

 ited North 'America, and migrated thence to the old world 

 probably via the Behring Isthmus, which at various times 



