TRANSACTIONS OF SECTION H. 777 



One of the most striking peculiarities of man when regarded from the structural 

 point of view is the relatively great size of his brain. Although with one or two 

 exceptions the several parts of the brain are all more or less involved in this 

 special development, it is the cerebral hemispheres Avhich exhibit the pre- 

 ponderance in the highest degree. This characteristic of the human brain is 

 rendered all the more significant when we consider that the cerebral hemispheres 

 cannot be loolced upon as being primitive parts of the brain. In its earliest con- 

 dition the brain is composed of three simple primary vesicles, and the cerebral 

 hemispheres appear in a secondary manner in the shape of a pair of lateral offshoots 

 or buds which grow out from the foremost of these primitive brain-vesicles. 



The offshoots which form the cerebral hemispheres are found in all vertebrates. 

 Insignificant in size and insignificant in functional value in the more lowly forms, 

 a steady increase in their proportions is manifest as we ascend the scale, until the 

 imposing dimensions, the complex structure, and the marvellous functional 

 potentialities of the human cerebral hemispheres are attained. In their develop- 

 ment the cerebr.al hemispheres of man rapidly outstrip all the other parts of the 

 brain until they ultimately usurp to themselves by far the greater part of the 

 cranial cavity. To the predominant growth of the cerebral hemispheres is due the 

 lofty cranial vault of the human skull ; to the diflerent degrees of development 

 and to the dilferent forms which they assume are largely due the variations in 

 cranial outline in different individuals and different races — variations in the deter- 

 mination of which the C'ranlologist has laboured so assiduously aud patiently. 



I think that it must be manifest to everj'one that the work of the Uraniologist, 

 if it is to attain its full degree of usefulness, must be founded upon a proper recog- 

 nition of the relation which exists between the cranium and the brain, or, in other 

 words, between the envelope and its contents. 



The cranium expands according to the demands made upon it by the growing 

 brain. The initiative lies with the brain, and in normal conditions it is questionable 

 if the envelope exercises more than a very subsidiary and limited influence upon 

 the form assumed by the contents. The directions of growth are clearlj' defined 

 by the sutural lines by which the cranial bones are knit together ; but these are so 

 arranged that they admit of the expansion of the cranial box in length, in breadth, 

 and in height, aud the freedom of growth in each of these diflerent directions has 

 in all probability been originally determined by the requirements of the several 

 parts of the brain. 



The base or floor of the cranium, supporting as it does the brain-stem or the 

 parts which possess the greatest phylngenetic antiquity, and which have not under- 

 gone so large a degree of modification in human evolution, presents a greater 

 uniformity of type and a greater constancy of form in different individuals and 

 different races than the cranial vault which covers the more highly specialised and 

 more variable cerebral hemispheres. 



To what extent and in what directions modifications in the form of the cranium 

 may be the outcome of restrictions placed on the growth of the brain it is difficult 

 to say. But, broadly speaking, I think we may conclude that the influence which 

 the cranium, under normal circumstances, independently exerts in determining the 

 various head-forms is trifling. 



When we speak therefore of brachycephalic or short heads, and dolichocephalic 

 or long heads, we are merely using terms to indicate conditions which result from 

 individual or racial peculiarities of cerebral growth. 



The brachycephalic brain is not moulded into form by the brachycephalic 

 skull ; the shape of both is the result of the same hereditary influence, and iu their 

 growth they exhibit the most perfect harmony with each other. 



Craniology has been called the ' spoiled child of Anthropology.' It is supposed 

 that it has absorbed more attention than it deserves, and has been cultivated with 

 more than its share of care, while other fields of Anthropology capableofyielding rich 

 harvests have been allowed to remain fallow. This criticism conveys a" very partial 

 truth. The cranium, as we have seen, is the outward expression of the contained 

 brain, and the brain is the most characteristic organ of man ; cranial peculiarities 

 therefore must always and should always claim a leading place jn the mind of thp 



