CHAPTER II. 



Tin-: IXCOMrETEXCY OF " NATURAL SELECTION " TO ACCOUNT 

 FOR THE INCIPIENT STAGES OF USEFUL STRUCTURES. 



^Ir. Darwin supposes tliat Natural Selection acts by slight variations. — 

 These must be useful at once. — DiHiculties as to the giratl'e ; as to 

 niiniicry ; as to the heads of flat-fishes ; as to the origin and constancy 

 of the vertebrate limbs ; as to whalebone ; as to the young kangaroo ; 

 as to sea-urchins ; as to certain processes of metamorphosis ; as to the 

 mammary gland ; as to certain ape characters ; as to the rattlesuake 

 and cobm ; as to the process of formation of the eye and ear ; as to 

 the fully developed condition of the eye and oar ; as to the voice ; as 

 to shell-tish : as to orchids ; as to ants. — The necessity for the simul- 

 taneous modification of many individuals. — Summary and conclusion. 



'' Natural Selection," simply and by itself, is potent to 

 explain the maintenance or the further extension and 

 development of favourable variations, which are at once 

 sufficiently considerable to be useful from the first to the 

 individual possessing them. But Natural Selection utterly 

 fails to account for the conservation and development of 

 the minute and rudimentary beginnings, tlie slight and 

 insignificant commencements of structures, however useful 

 those structures may afterwards become. 



Now, it is distinctly enunciated l)y Mr. Darwin, that the 

 spontaneous variations upon wliich his theory depends are 

 individually slight, minute, and insensible. He says,' 

 ^ "Animals and Plants under Domestication," vol. ii. p. 192. 



