CHAP. XXIII. ] 



OF THE HUMAN BRAIN, 



439 



through it. " The intra- ventricular portion consists of a 

 deposit or bed of soft grey matter, not intermixed with 

 distinct fibres visible to the naked eye, thicker and wider 

 anteriorly in the anterior cornu of the ventricle narrow- 

 ing to a point posteriorly. It rests upon the radiating 

 fibres of the tegmentum and thalamus which pass on- 



Fio. 157. Transverse section of the Cerebrum, just behind Infuudibulnm. 

 S V, Intra-ventricular, and SX, Extra- ventricular Corpus Striatum. Th, Thalamus. 

 re, Crusta, andrt, Tegmentum of Crus Cerebri; R, radiating expansion of white 

 fibres (' corona radiata ') ; re, r t, and R together form what has been called the 

 'internal capsule' of the Lenticular Nucleus. Cx, 'external capsule' (including 

 the Claustrum) ; C, Corpus Callosum ; FS', Fissure of Sylvius; LMG, Longitudinal 



Marginal Gyrus. S M G, S M G', Sylvian Marginal Gyrus ; , indicate lines of 



derivation of fibres of Corpus Striatum ;...., Fibres of distribution of Thalamus. 

 (Broadbent.) 



wards beneath it to the hemisphere proper." Between 

 the bundles of radiating fibres this upper and anterior 

 portion is continuous with the lower and outer ' extra- 

 ventricular ' portion of the Corpus Striatum, which is more 

 bulky than the part already described, though it is, like it, 

 also larger in front than behind. It is a somewhat pear- 

 shaped mass of soft grey matter, bounded above and 



