430 PROCEEDINGS OF THE AMERICAN ACADEMY 



intermediate between the two. May not all the forms which seem to 

 link one species with another be explained on the same principle ? 



4. The use of the word accidetital in this connection is not warrant- 

 able. For the question will resolve itself at last into a question of de- 

 sign, and the use of this word is therefore a begging of the matter at 

 issue. 



5. If geological investigations showed an ascending series, while the 

 lower forms wei'e extinguished, there might be some ground for this 

 theory ; though even then it might be difficult to conceive why in all 

 cases the intermediate forms were wanting in the great record. But 

 forms of the lowest type are as frequent now as ever ; the Lingula lives 

 at the present day in perfect harmony with the Clam, which should have 

 superseded it. 



6. The word indefinite, as applied to time, has no clear meaning to 

 distinguish it from infinite. A million or ten millions of years would 

 not be an indefinite period. Now we know some of the properties of 

 the infinite, as in the case of the summation of series; but the idea of 

 infinity itself we cannot grasp, and we have no right to invoke it in the 

 solution of any finite question. 



7. Long as are the periods established by geology, the author is 

 obliged to resort to a much longer time to account for the development 

 of such a curious and exquisite organism as that of the eye from a mere 

 nervous thread accidentally sensitive to light. For in the earliest 

 stratified rocks the Trilobites are already gifted with complex organs of 

 vision, and that comparatively modern animal, the Ichthyosaurus, has 

 an eye that any reptile at the present day might envy. 



8. A yet more serious objection lies against the evidently forced and 

 painful attempt to trace the development of reason from the lower forms 

 of animal instinct. With regard to man, so recent has been his intro- 

 duction on the earth, that we might reasonably expect to find the inter- 

 mediate forms which must have existed between him and the anthropoid 

 apes. 



9. The whole theory rests on the assumption, that there may be forms 

 more favored and better fitted to succeed in the struggle for life, than 

 those originally created. But is this proved ? Observe, that as fast as 

 any species, by this theory, improves, just so fast its enemies must im- 

 prove also. While Nature avails itself of an accidentally harder pro- 

 boscis, to enable an insect, now become a borer, to lay its eggs within 



