Likenesses ; or, Philosophical Anatomy 267 



e pelvis of a certain lion affected with a kind of rheuma- 

 tism Sir James remarked a deposit which had formed a 

 pattern more complex and irregular than the spots upon a 

 map, while not one spot or line on one side failed to be 

 represented with daguerreotype exactness on the other. 

 He also considers that parts which are serially, as well as 

 those which are laterally homologous, are likely to be 

 affected in a similar manner. Such serially homologous 

 parts are the back of the hand and the corresponding 

 surface of the foot, and these are likely to be both modified 

 in the same manner, as also are the palms and soles, the 

 elbows and knees, together with the other serially corre- 

 sponding parts of the arms and legs. 



What explanation can be offered of these phenomena? 

 To say that they exhibit a 'nutritional relation,' brought 

 about by a ' balancing of forces,' is but another statement of 

 the fact, and affords no explanation of it whatever. The 

 changes are, of course, brought about by a 'nutritional' 

 process, and the symmetry is undoubtedly the result of a 

 * balance of forces ' ; but to say so is to affirm a truism. The 

 question is. What is the cause of this ' nutritional balancing ' ? ^^^ 

 It seems impossible not to concede the existence of an 

 internal force. If this power be referred, as it seems Mr. 

 Spencer would refer it, to certain physiological units of 

 which he imagines each organism to be composed, it must 

 none the less be recognised as an innate power, possessed by 

 such units, of inheriting the effects of ancestral modification. 

 It is not easy to see the advantage of Mr. Spencer's reference. 

 It seems easier, simpler, and more consonant with known 

 facts, to recognise in each organism as a whole (which is 

 visibly a unity) an innate power, tending to development 

 of a special kind, though the actual results of the developing 

 force must be modified by the external conditions which 

 happen to exist in each case during the process of development. 



