Lect. v.] adaptive changes. 131 



a very simple form of tooth-pattern, much like that still 

 seen in the Marsupials, but the teeth were in great 

 number, and often with no interspaces. The digits 

 gradually began to abort ; the innermost (the hallux and 

 the pollex) going first ; but no sign was shown then 

 of such feet as we see now in the even- and odd-toed 

 types of our noble, existing, hoofed forms. The Cow, 

 that parts the hoof, cleaving the foot into two equal por- 

 tions, and the Horse, who brings his springy weight down 

 upon a single digit on each foot — a digit that has drawn 

 the life out of the others — such forms as these had no 

 existence until near to the time when the ruler of the 

 beasts appeared. 



In the olden time the term proboscidean would have 

 been applicable, not to an Order, but to certain Genera. 

 Even now this elongation of the double nose-tube, and 

 its segmentation into a ringed structure, is not confined 

 to the Elephants, as I shall soon show. 



If there were any supra-mundane biologists watching 

 the evolution of forms on our planet at this time they 

 would see the first promise of defensive horns, and 

 the gradual specialisation of certain teeth for offensive 

 and defensive purposes. If we suppose that such 

 watchers of creation existed, and that they had joy 

 <at the sight of those strange beasts of an early age, 

 then what must have been their feelings when they 

 saw, at last, the forms with which we are all familiar 

 — Antelopes, Oxen, Deer, Bears, Wolves and Lions ? 



