246 Form and Color in Nature. 



with approval, believes in natural selection and pammixis, 

 or the combination by marriage of varying types alone, as 

 the causes of the origin of species, and wholly repudiates 

 the inheritability of acquired characters. He develops a 

 peculiar theory of the continuity of the germ-plasm that a 

 portion of the original germ itself and not a new germ 

 passes from individual to individual in the line of descent, 

 and that modification comes alone through the crossing of 

 varieties in the germ. That this is an absolutely unproved, 

 if not an absolutely unprovable, hypothesis is perhaps its 

 weakest feature. Possibly the, best sentences in Mr. James 

 Hinton's curious, interesting, and very disappointing book, 

 Life in Nature, are these : " Let it be assumed, for argu- 

 ment's sake, that all the phenomena of life could be traced 

 back to chemical and mechanical powers, what would fol- 

 low? Simply that all the wonder and admiration with 

 which we now regard the living body would be extended 

 with increased intensity and elevation to those powers which 

 we call chemistry or mechanics, but which we would then 

 perceive we had entirely underestimated." Whatever dif- 

 ferences there may be in regard to more or less, I suppose 

 that most of our men of science of good standing are agreed 

 that the struggle for existence, variation in individuals from 

 whatever cause, natural selection, and the survival of the 

 fittest, are stages of the most important process in the de- 

 velopment of species. Variation in minor particulars is 

 shown to be of the widest occurrence. Those variations 

 which prove useful in any way tend so far to give the indi- 

 viduals in which they occur an advantage over others, and 

 so enable them to leave posterity ; and a repetition of the 

 same variations, accompanied by similar advantages, -tends 

 toward permanency and toward an increase of the acquired 

 peculiarities. 



If I should now attempt to do badly what was so mag- 

 nificently done last winter by Mr. Kimball in relation to an 

 important branch of the development of form, I certainly 

 should not thereby establish a reputation for wisdom. If 

 there be any present who failed to hear Mr. Kimball's fas- 

 cinating essay upon The Evolution of Arms and Armor the 

 finest piece of work which has ever been done in this field 

 I should advise him or her to lose no time in reading it. 

 Its burden is the burden of war : how the struggle for 

 existence led to attack and defense, and these to altera- 

 tions in structure for the one purpose or the other, each 



