exte^sio:n's of darwixism 



28' 



proboscis. Tlie elephants thus arose as a kind of aftertlioiiglit 

 from a group of quadrupeds that were rapidly approaching tlicir 

 doom." (See figures in last chapter, p. :^-")7.) 



This last is a specially interesting case, because it is the 

 only^ one in which, without change of general environnifnt, 

 or apparently of habits, a highly developed animal has re- 

 traced its latest steps, and then advanced in a new line of de- 

 velopment, leading to the wonderful trunk and the cnurmous 

 tusks of the modern elephant, as explained in Chapter XIT. 

 That these have now attained the maximum of useful growth 

 is indicated bv the fact that amoni>: the extinct fonus are those 

 in which they are developed to an unwieldy size, as in Elephas 

 ganesa of Xorth-West India, whose slightly curved tusks, some- 

 times nearly 10 feet long, must have put an enormous strain 

 upon the neck, and the mammoth, whose greatly curved tusks 

 were almost equally heavy. 



Excessive Development of Lower Animals before Extinction 



My friend Professor Judd has called my attention to the 

 fact that many of the lower forms of life exhibited similar 

 phenomena. The Trilobites (primitive crustaceans) which 

 were extremely abundant in the Pala?ozoic rocks, in their last 



Fig. 96. — Conocoryphc sultzcri. 

 Upper Cambrian. 



Fio. 97. — Paradonides bohcmicus. 

 Upper Cambrian. 



