136 , REPORT — 1875. 



Darwinian theory to the utmost possible extreme, the action of external agents 

 infers the existence of something acted on ; and the less directly they act, the more 

 importance must be given to the hereditary or internal element. We are there- 

 fore presented with a formative force, which exhibited itself in very simple trains 

 of phenomena in the first beginnings of life, and now is manifested in governing the 

 complex growth of the highest forms. We are set face to face with that formative 

 force, and are obliged to admit its inherent capability of changing its action ; and 

 that being the case, is it more of an assumption to declare that the changes are all 

 accidental and made permanent by accident of external circumstance, or to con- 

 sider that it has been the law proper to this force to have been adequate to raise 

 forms, however liable to modification by external circumstances — to raise them, I 

 say, from the simple to the complex, acting through generations on the face of the 

 earth, precisely as it acts in the evolution of a single egg into an adult individual ? 

 This is that formative force which has been elaborately shown by Mr. Darwin, in 

 launching his theory of " pangenesis," not only to be conveyed through whole or- 

 ganisms and their seed, but to pervade at all times the minutest particles of each ; 

 and I merely direct attention to the fact that its extension over the whole history 

 of life on the globe must be granted, and ask if, in the range of forms which furnish 

 at the present day an imperfect key to the ages which are past, there is not exhi- 

 bited a development comparable, in its progression to definite goals, with what is 

 shown in the life of a single plant or animal. For my own part, I am fully con- 

 vinced of a unity of plan running through animal forms, and reaching, so far as the 

 main line is concerned, its completion in the human body. I confess that I think 

 that there is evidence that animal life has reached its preordained climax in 

 humanity ; and I cannot think it likely that, as myriads of years roll on, descendants 

 differing in toto from man will be developed. To argue the subject would be to 

 enter on the largest subjects of morphological anatomy, and on speculations on 

 which agreement could not be expected. Even, however, in the nature of the 

 variations in the human race there seems to be some evidence that the progress of 

 evolution is to be traced from man, not to other animal forms yet to appear, but, 

 through his psychical nature, into the land of the unseen. Those variations, keep- 

 ing out of view differences of bulk and stature, which appear to have some relation 

 to geogi-aphical position, are principally to be found in the head, the part of the body 

 most closely connected with the development and expression of the mental cha- 

 racter ; and I may mention that when, some years ago, my attention was directed 

 to the variations of the skull, the only part whose variations in difierent races I have 

 had opportunity of studying with any degree of minuteness, I became satisfied that 

 in uncivilized races there might be distinguished skulls which had undergone here- 

 ditary degeneration, others which had reached the most advanced development 

 possible for them, and a third set, notably the Kaffirs, with large capabilities for 

 improvement in the future. Indeed it is beyond doubt that there is a limit for 

 each type of humanity beyond which it cannot pass in the improvement of the 

 physical organization necessary for mental action*. 



There are also some curious indications in human structure of the formative force 

 neariug the end of its j ourney. In the details of the skeletons of other animals one sees 

 the greatest precision of form ; but there are various exceptions to this neatness of finish 

 in the skeleton of man, and they are found in parts speciallj' modified in connexion 

 with the peculiarities of his development, and not requiring exactness of shape forphy- 

 siological pui-poses ; while, on the other hand, physiognomical moidd and nicety of 

 various physiological adaptations are found in perfection. Look at the variations 

 in the breast-bone, especially at its lower extremity, which is never shapely, as it 



* I aUude to the circumstances — that under the influence of civilization the length of 

 the base of the skull does not increase, but positively decreases ; that the proportion of the 

 extent of the arcli to the base has strict hmits ; that the curvature of the base in some un- 

 civilized races falls slightly short of the normal ; that in others it transcends the normal 

 by a pecidiar process of degeneration between the sphenoid and ethmoid ; and that increased 

 capacity of the cranial cavity in the progress of civilization is obtained almost entirely by 

 increase of breadth and by the rounding out of those flat surfaces above and below the 

 temporal ridges vrhich give savage skidls a roof-like appeai'ance. (See "Inquiry into Vari- 

 ations of Skull,,"' Phil. Trans. 1870.) 



