PERSONAL APPEARANCES IN HEALTH AND DISEASE. 49 



In proportion as the fluid is formed the capacity of these 

 ventricles increases, and the whole bulk of the brain is 

 enlarged. Then also the cavity* of the ^ 



skull enlarges and the head assumes a 

 rounded shape, in which the cranial part 

 is out of all proportion to the small facial 

 part in a painfully grotesque manner 

 (Fig* 8). A comparison of this form of 

 enlargement of the head with that pro- 

 duced by the perverted growth of the 

 cranium in rickets (Fig. 9) shows that in hydrocephalus 

 the skull tends to the globular form, whereas in rickets, 

 the square-shaped protuberant forehead and 

 the projecting occiput are surmounted by 

 almost a flattened vertex. Sometimes, in 

 consequence of this hydrocephalus, the 

 cranium attains an enormous size. Nor 

 does it always, although very frequently, 

 terminate in early death. The progress may 

 be arrested, but the enlargement never subsides, and 

 throughout life the rounded form of the head may be 

 retained. Often bones not present in the normal skull 

 are developed to fill up the spaces of membrane. 



Here we may turn aside for a moment to glance at 



* Outline of hydrocephalic head. 



f Outline of ricketty head. The deformity in this instance is not 

 very pronounced. 



