272 APPENDIX. 



which was scattered over cyclopedias, translations of learned 

 secieties, and other costly books." 



Mr. Tuttle, in a letter to me (a few words of which have 

 been interpolated in the foregoing article), in substance says : 



" At the close of the Eocene period there were three distinct 

 types of animals descended from a common ancestor that are 

 now represented by the horse, tapir, and rhinoceros.* Let us 

 suppose that a pair of animals gave birth to the offspring which 

 were to be the parents of these three types. What would be 

 the process of development ? These animals, with their mates, 

 by some means get separated. The parent of the future tapir 

 goes one way ; that of the rhinoceros stays at home, while he 

 who is to beget the horse wanders away from the marshes and 

 rivers to the dryer land. Circumstances over which he has no 

 adequate control place him where alligators, crocodiles, and 

 other animals that he has been accustomed to attack with his 

 tushes are absent. His feet, which are many-toed, broad, and 

 adapted to walking in the mud, now tread hard soil ; his canine 

 teeth, which were used in tearing flesh, now find little employ- 

 ment ; his neck, from constant stretching as he crops the foliage 

 of the bushes, lengthens ; a more rapid gait is acquired by a 

 gradual contraction of the toes and the lengthening of the legs, 

 and eventually this modified animal becomes a horse. Thus is 

 told in a few words what I believe has been going on in the 

 course of hundreds of thousands, perhaps millions of years." 



It is noteworthy that a young man like Mr. Tuttle should 

 entertain views similar to those of such an experienced evolu- 

 tionist as Prof. Cope. It is not difficult to believe that the 

 bear-like Amblypoda, which Prof. Cope thinks were the com- 

 mon progenitors of the horse, tapir, rhinoceros, elephant, &c., 

 were carnivorous, and there certainly is some analogy between 

 the supposititious animal just described by Mr. Tuttle and the 

 Amblypoda. Change of food was probably as instrumental in 

 producing the great physical changes in early fossil animals as 

 change of habitat and climate. And change of food does not 



* Compare with quotation from Prof. Huxley in third note, pp. 65-66; 

 also with same from Prof. Owen, pp. 106-7. 



