VI.] SPECIES AND TIME. I45 



reptiles passes to the birds last named from the Dinosauria 

 rather than from the Pterodactyls, through Archeopteryx- 

 like forms to the ordinary birds. Finally, he has thrown 

 out the suggestion that the celebrated footsteps left by 

 some extinct three-toed creatures on the very ancient sand- 

 stone of Connecticut were made, not, as hitherto supposed, 

 by true birds, but by more or less ornithic reptiles. But 

 even supposing all that is asserted or inferred on this sub- 

 ject to be fully proved, it would not approach to a demon- 

 stration of specific origin by mi?iide modification. And 

 though it harmonizes well with " Natural Selection," it is 

 equally consistent with the rapid and sudden develoj)ment 

 of new specific forms of life. Indeed, Prof. Huxley, with a 

 laudable caution and moderation too little observed by 

 some Teutonic Darwinians, guarded himself carefully from 

 any imputation of asserting dogmatically the theory of 

 " Natural Selection," while upholding fully the doctrine of 

 evolution. 



But, after all, it is by no means certain, though very 

 probable, that the Connecticut footsteps were made by 

 very ornithic reptiles, or extremely sauroid birds. And it 

 must not be forgotten that a completely carinate * bird (the 

 Archeopteryx) existed at a time, when, as yet, we have no 

 evidence of some of the Dinosauria having come into being. 

 Moreover, if the remarkable and minute similarity of the 

 coracoid of a pterodactyl to that of a bird be merely the 

 result of function, and no sign of genetic affinity, it is not 

 inconceivable that pelvic and leg resemblances of Dinosau- 

 ria to birds may be functional likewise, though such an ex- 

 planation is, of course, by no means necessary to support 

 the view maintained in this book. 



But the number of forms represented by many individ- 

 uals, yet by 7io transitional ojies^ is so great, that only two 



* A bird with a keeled breastbone, such as almost all existing birds 

 possess. 



7 



