314 THE TROGLODYTES. 



mamniotb, {Elephas primigcnius.) Of the otbei^ extinct species of the 

 l^eriod it would be superilnous to speak. The reindeer and several other 

 migrated animals are found in this fauna, but are rare, and a large num- 

 ber of persistent species had already made their appearance. 



Of all these animals, the most remarkable, the most powerful in strength 

 and numbers, was the mammoth. Protected from the cold by a thick 

 covering of fur, and provided with formidable means of defense against 

 its enemies, it prospered and multiplied; it spread and dominated over 

 all the earth, so that the first part of the Quaternary period, which cor- 

 responds with the lower levels of the valleys, may well be called the 

 age of the mammoth. At that time every condition was favorable to 

 the prosperity of this animal. But in time there were changes which 

 led to its decadence. An elevation in the temperature allowed the exten- 

 sion of numerous herbivorous species hitherto restrained in their devel- 

 opment. The reindeer, the horse, the ox, and the bison multiplied. These, 

 his powerful rivals, disputed with the mammoth his vegetable nutrition, 

 and with him commenced the struggle for existence. Already he saw 

 opposed to him the power of man, which under the ameliorated condi- 

 tions of climate was sufficient to declai'e war against him, and finally 

 this same climate which was so favorable to his enemies and rivals became 

 directly prejudicial to his organization, intended for a boreal tempera- 

 ture. 



Thus the mammoth, once so important in the first jiart of the Quater- 

 nary period, commenced to decline. He ceased to be the predominant 

 species of the fauna, and as to the other animals which formed his ancient 

 cortege, many yielded with him to the destructive influence of the 

 changed temperature, and decreasing in numbers we see them slowly, 

 one after the other, disappear. Some, it is true, survive, and may pro- 

 long their existence to the end of paleoutological time, but their reign 

 is over. 



Thus about the middle of the Quaternary period there was an inter- 

 mediate age, corresponding with the mean levels of the valleys ; an age 

 when several species contemporary with the mammoth had already be- 

 come extinct, and others, which had almost disappeared, were repre- 

 sented by only a few individuals, while animals better adapted to the 

 changed conditions prospered. Prominent among the latter was the 

 reindeer, {Cervus tarandus,) but it was not until the following period that 

 it attained its full imiiortance. 



The fauna of the intermediate age has no especial paleoutological 

 characteristics. It is distinguished less by the nature of the species 

 than by the relative proi)ortion of their representation. Certain ani- 

 mals of the age of the mammoth no longer existed, but others were fourKl 

 here and there. The mammoth, although reduced in numbers, had not 

 yet become rare, while the reindeer, the stag, the horse, and the ox had 

 become common. 



This intermediate age gradually yielded to the third and last age of 



