stu 



THE LATERAL VENTRICLE. 



633 



study of a cast of its interior 

 (Figs. 561 and 545, p. 618). 

 It is usual to describe it as 

 being composed of a body and 

 three horns, viz. an anterior, a 

 posterior, and an inferior horn. 

 The cornu anterius is that part 

 of the cavity which lies in 

 front of the interventricular 

 foramen. The body or pars 

 centralis is the portion of the 

 ventricle which extends from 

 the interventricular foramen 

 to the splenium of the corpus 

 callosum. At this point the 

 posterior and inferior horns 

 diverge from the posterior 

 part of the body. The cornu 

 posterius curves backwards and 

 . medially into the occipital 

 lobe. It is very variable in 

 its length and capacity: the 

 chief reason for this variability 

 is that adhesions between the 

 walls of this part of the ven- 

 tricle 'are of common occur- 

 rence. The cornu inferius 

 proceeds with a bold sweep 

 round the posterior end of the Fra. 561. DRAWING TAKEN FROM A CAST OF THE VENTRICULAR 

 thalamus, and then tunnels in SYSTEM OF THE BRAIN, as seen from above. (After Ketzius.) 

 a forward and medial direction Vent. III. Third ventricle. Vent. IV. Fourth ventricle. 



the temporal lobe KSP - 



through 



Longitudinal 

 fissure 



Corpus callosum 

 Lateral ventricle 

 Column of fornix 

 Chorioid plexus. 



Foramen inter- 

 ventriculare 



Septum pellucidum 



towards the tem- 

 poral pole. 



The early 

 foetal lateral ven- 

 tricle is very 

 capacious and 

 presents an 

 arched or semi- 

 lunar form. It is 

 composed of parts 

 which correspond 

 to the anterior 

 horn, the central 

 part and the in- 

 ferior horn, and 

 there is little or 

 no demarcation 

 between them. 

 The posterior 



horn is a later 



"tSTS-/ lllvtfuP^ production. It 



Nucleus lentiformis / COmeS into CXlst- 



ciaustrum ence as a diver- 



FIG. 562. FRONTAL SECTION THROUGH THE CEREBRAL HEMISPHERES so as to cut ticulum or elon- 

 through the anterior horns of the lateral ventricles, through which the central CTn t fir q pouch 



part of the ventricles, the columns of the fornix, and the interventricular 

 foramina can be seen. 



which grows 



