815 



Tacl tliat tliis lairiina is ricfily ]iro\ iüe<i willi blood-vessels, a poiiil 

 to which I shall retuni later. It extends from the ventricular surface 



Tr Sep rues 

 Trfrep 



Com inCeTep 



Fig XI 



Fig XII 



of tiie corpus striatum medially to an external groove marking the 

 interval t)etweeii the hyperstriatum and mesostriatum ventrallj. 

 Therefore this lamina separates the two pai'ts not only dorsalU hut 

 laterally. Kor this reason as Ariëns K.appkhs has suggested (!9'22) 

 it is preferable to employ the term lamina medvllaris e,vterna, in 

 referring to this fibre zone. The fibres constituting it, which are 

 connected on tlie one hand witii the thalamus (vide infra), radiate 

 laterally between columns of cells of the hyperstriatum. This confers 

 a striated appearance upon this structure especially in its ventro- 

 lateral part. 



nied.e» 



Nocll 



Fig Kill 



Fig XIV 



The ectostriatum which lies between (lie mesostriatum and liyjier- 

 striatum and is recognisable by the naked-eye on account of its 

 infill ration by fibres, and microscopically by the [u-esence of large 



