10 DARWIXIAFA. 



tains the essence of the whole, yet much of the aroma 

 escapes in the treble distillation, or is so concentrated 

 that the flavor is lost to the general or even to the 

 scientific reader. The volume itself — the proof-spirit 

 — is just condensed enough for its purpose. It will 

 be far more widely read, and perhaps will make 

 deeper impression, than the elaborate work might 

 have done, with all its .full details of the facts upon 

 which the author's sweeping conclusions have been 

 grounded. At least it is a more readable book : but 

 all the facts that can be mustered in favor of the 

 theory are still likely to be needed. 



Who, upon a single perusal, shall pass judgment 

 upon a work like this, to which twenty of the best 

 years of the life of a most able naturalist have been 

 devoted ? And who among those naturalists who 

 hold a position that entitles them to pronounce sum- 

 marily upon the subject, can be expected to divest 

 himself for the nonce of the influence of received and 

 favorite systems % In fact, the controversy now opened 

 is not likely to be settled in an off-hand way, nor 

 is it desirable that it should be. A spirited conflict 

 among opinions of every grade must ensue, which — 

 to borrow an illustration from the doctrine of the book 

 before us — may be likened to the conflict in Nature 

 among races in the struggle for life, which Mr. Dar- 

 win describes ; through which the views most favored 

 by facts will be developed and tested by " Natural 

 Selection," the weaker ones be destroyed in the pro- 

 cess, and the strongest in the long-run alone survive. 



The duty of reviewing this volume in the Ameri- 

 can Journal of Science would naturally devolve upon 



