THE ARREST OF THE BODY. 113 



head and face which cannot be carried further than 

 in Man. For the mode in which the cranial cavity is 

 gradually increased in size is a regular one, which 

 may be explained thus : we may look on the skull as 

 an irregular cylinder, and at the same time that it is 

 expanded by increase of height and width it also 

 undergoes a curvature or bending on itself, so that the 

 base is crumpled together while the roof is elongated. 

 This curving has gone on in Man till the fore end of 

 the cylinder, the part on which the brain rests above 

 the nose, is nearly parallel to the aperture of com- 

 munication of the skull with the spinal canal, i. e., the 

 cranium has a curve of 180 or a few degrees more or 

 less. This curving of the base of the skull involves 

 change in position of the face bones also, and could 

 not go on to a further extent without cutting off the 

 nasal cavity from the throat . . . Thus there is 

 anatomical evidence that the development of the ver- 

 tebrate form has reached its limit by completion in 

 Man." 1 



This author's conception of the whole field of living 

 nature is so suggestive that we may continue the quo- 

 tation: "To me the animal kingdom appears not in 

 indefinite growth like a tree, but a temple with many 

 minarets, none of them capable of being prolonged 

 while the central dome is completed by the structure 

 of man. The development of the animal kingdom is 

 the development of intelligence chained to matter ; 

 the animals in which the nervous system has reached 

 the greatest perfection are the vertebrates, and in Man 

 that part of the nervous system which is the organ of 



1 Prof. J. Cleland, M.D., F.R.S., Journal of Anatomy, VoL 

 xviii., pp. 360-1. 



