MODEL OF MEDULLATED TRACTS IN BABY 's BRAIN 135 



considered, there are two curvedsheetsof fibres which spread out 

 from the lateral surface of the anterior limbs of the internal capsule 

 and these two shells of fibres separate the parts of the internal 

 capsule. Thus, from the standpoint of the corpus striatium, there 

 are three sheets of fibres, one separating the caudate nucleus from 

 the putamen, the other two separating the three parts of the len- 

 ticular nucleus, and these three sheets of fibres meet in the sheet 

 of fibres which makes up the knee of the internal capsule. There 

 is no doubt that the form of the internal capsule can be made much 

 plainer by models of the medullated bundles in series of later 

 stages. 



