166 FOSSIL EEMAINS OF MAN. 



between Man and the man-like apes ? Or, on the other 

 hand, does neither depart more widely from the average 

 structure of the human cranium, than normally formed 

 skulls of men are known to do at the present day ? 



It is impossible to form any opinion on these questions, 

 without some preliminary acquaintance with the range of 

 variation exhibited by human structure in general — a sub- 

 ject which has been but imperfectly studied, while even 

 of what is known, my limits wdll necessarily allow me to 

 give only a very imperfect sketch. 



The student of anatomy is perfectly well aware that 

 there is not a siugle organ of the human body the struc- 

 ture of which does not vary, to a greater or less extent, in 

 different individuals. The skeleton varies in the propor- 

 tions, and even to a certain extent in the connexions, of its 

 constituent bones. The muscles which move the bones 

 vary largely in their attachments. The varieties in the 

 mode of distribution of the arteries are carefully classified, 

 on account of the practical importance of a knowledge of 

 their shiftings to the surgeon. The characters of the brain 

 vary immensely, nothing being less constant than the form 

 and size of the cerebral hemispheres, and the richness of 

 the convolutions upon their surface, while the most change- 

 able structures of all in the human brain, are exactly those 

 on which the unwise attempt has been made to base the 

 distinctive characters of humanity, viz. the posterior cornu 

 of the lateral ventricle, the hippocampus minor, and the 

 degree of projection of the posterior lobe beyond the cere- 

 bellum. Finally, as all the world knows, the hair and 

 skin of human beings may present the most extraordinary 

 diversities in colour and in texture. 



So far as our present knowledge goes, the majority of 

 the structural varieties to which allusion is here made, are 

 individual. The ape-like arrangement of certain muscles 



