THE TIME ELEMENT. 101 



represent existing species. These figures show 

 no specific variation or any tendency thereto, 

 although more than 200 generations of men, 

 and 2000 of most of the other animals rep- 

 resented, have passed since they were de- 

 picted. No doubt 5000 years is but a small 

 fraction of the existence of life on our 

 globe, but we have a far longer experience. 

 According to Darwin, new species did not 

 arise per saltum, but were slowly evolved 

 by the accumulation of small beneficial 

 differences that from time to time appeared, 

 aided by secondary causes. Specific varia- 

 tion has thus been in progress since the 

 beginning of the present geological epoch, 

 and, we may infer, in many species, if not 

 in all. There ought, therefore, to be many 

 examples of new species in various stages 

 of development. But neither naturalists 

 nor biologists have discovered any trans- 

 itionary forms such as the Darwinian theory 

 demands. 



So far, therefore, as there is evidence, it is 

 against the hypothesis that specific variation 

 has arisen during vastly extended periods of 

 time. 



