CHAP, vii EVOLUTION IN DARWIN 73 



so long as beauty is not developed at the sacrifice of 

 useful qualities, sexual selection will hasten the evolu- 

 tionary process along lines on which it has already 

 begun to move along the line of beauty, if not in- 

 contestably along the line of strength or aggregate 

 fitness. 



Another supplement to Darwin's central doctrine 

 is what may conveniently be termed use-inheritance. 

 This played a great part in the evolutionary theories 

 of Lamarck, along with a still more questionable 

 doctrine, that of direct adjustment of the organism 

 to its environment. As the comic song puts it, the 

 giraffe got a long neck by stretching to reach the 

 upper branches. That is scarcely Darwinism ; it is 

 much nearer Lamarckism. The Darwinian giraffe 

 happened to be born with a longer neck than the 

 remainder of his family, and consequently outlived 

 them all in a time of scarcity, and was the only 

 giraffe who transmitted his qualities to offspring. 

 If the giraffe stretched its muscles and its vertebrae 

 to their utmost, and begat a son whose neck, un- 

 stretched, was as tall as the parent's in his habitual 

 tiptoe attitude, that would be use-inheritance one- 

 half of Lamarck's doctrine, and an accredited though 

 a subordinate portion of Darwin's. If, however, the 

 hungry giraffe organised in itself by some means or 

 other an extra joint, or an extra set of muscles, or, 

 as would probably be necessary, both, that would be 

 a grotesque illustration of the second half of La- 

 marck's theory, of direct action by environment in 

 the way of modifying an organism ; a grotesque 

 illustration of a sufficiently grotesque belief. At 

 times, it is said, Darwin writes as if he were willing 



