JULT ], 1904.] 



SCIENCE. 



21 



man contemporaneous with the dinosaur, al- 

 though it is not so stated in the text.' 



The attempt to avoid many words un- 

 familiar to children led to the use of the 

 term ' horse ' on pages 66 and 67 where 

 ' mammal ' or ' ancestor of the horse ' would 

 have been more exact. The lesson in question 

 was intended merely to give some such general 

 conception as Professor N. S. Shaler gives in 

 his chapter on the horse in 'Domesticated 

 Animals,' pages 58-9, where he states : " In 

 the first stages of the Tertiary period, in the 

 age when we began to trace the evolution of 

 the suck-giving animals above the lowly grade 

 in which the kangaroos and opossums belong, 

 we find the ancestors of our mammalian series 

 all characterized by rather weakly organized 

 limbs fitted, as were those of their remote 

 kindred, the marsupials, for tree-climbing, 

 rather than for running over the surface of 

 the ground. The fact is that all the creatures 

 of the great clan acquired their properties of 

 tody in arboreal life, and with such relatively 

 small and light todies as were fitted for tree- 

 clinibing." 



In so far as the illustration on page 67 con- 

 veys the idea that the remote ancestors of the 

 horse and other mammals once lived in prox- 

 imity to dinosaurs and were preyed upon by 

 these creatures, it is true to the facts. Its 

 defects consist in the fact (1) that the form 

 of the mammal in question resembles too 

 closely that of the Eocene horse, and (2) the 

 hind limbs of the dinosaur are not as long as 

 the skeletons indicate. 



Although the dinosaur in question lived in 

 the Jurassic period, as Dr. Case states, car- 

 nivorous dinosaurs were abundant in the Cre- 

 taceous and did not become extinct until the 

 end of that period. When this fact is taken 

 into account, and when it is remembered 

 that the most eminent paleontologists still ex- 

 pect to find in the Cretaceous rocks forms 

 intermediate between the Jurassic mammals 

 and the Eocene types, the reader can better 

 appreciate the point of view of the author in 

 presenting the lesson as it appears in the 

 first edition. But the illustration is defective 

 and it will not appear in the second edition. 

 The two lessons on the wild horse, including 



the remote ancestors of the horse, have been re- 

 vised, and although the ideas used are sub- 

 stantially the same, it is hoped that they are 

 expressed in a form which will not offend the 

 genuine student of science. It must be re- 

 membered, however, that the nature of the 

 work precludes the use of technical terms. 



The horses represented in the illustration 

 on page 62 are intended for Pleistocene horses 

 and are briefly described at the foot of page 

 70 and on page 71. It may be due to the 

 stripes, which are hypothetical, and to his 

 interpretation of the perspective of the picture, 

 that have led Dr. Case to interpret the horses 

 as Eocene forms. Although this picture is 

 not incorrect, it will be replaced by one which 

 can not be interpreted in such a way. 



Had Dr. Case read the text more carefully 

 he might still be in doubt regarding the time 

 relations of the dinosaur and the ancestors of 

 the horse on account of my use of the term 

 ' horse ' on pages 66 and 67. But he surely 

 could not have failed to see that man's rela- 

 tion to these primitive forms is distinctly 

 stated, even though technical terms are 

 avoided. For instance, the first line of the 

 text quoted by Dr. Case should make clear 

 that the animal described in the following 

 lines lived long before man appeared. Again, 

 at the foot of page 70 and the top of page 71 

 the form of the horse which was contempo- 

 raneous with man of the mid-Pleistocene 

 period is clearly stated. Had this not been 

 sufficient. Dr. Case could have found two notes 

 of warning against such an interpretation as 

 he has made, on pages 146 and 154. 



The real evidence, then, upon which the 

 criticisms of Dr. Case thus far considered rest, 

 is this : The defects pointed out in the illus- 

 tration on page 67, and the use of the term 

 ' horse ' in a sense wide enough to include the 

 remote ancestors of the horse. The evidence 

 which he has neglected is the text itself. 



In view of the well-established and readily 

 available statements concerning the discoveries 

 of Professor Cope in the United States, and 

 Professor Boyd Dawkins in Europe, with 

 reference to the hairy mammoth and the sabre- 

 toothed Felis (Machairodus) , it is difficult to 

 understand how Dr. Case could venture the 



