296 PRACTICAL ANATOMY. 



anteriorly, the two foramina of Monro ; bounded in 

 front by the anterior pillars of the fornix ; behind, by 

 the anterior extremities of the optic thalami. Each trans- 

 mits the choroid plexus. The aqueduct of Sylvius leads 

 from the third to the fourth ventricle ; it is lined by 



FIG. 129 HORIZONTAL SECTION OF BRAIN, SHOWING THIRD VENTRICLE. 



gray matter, and perforates the base of the tubercula 

 quadrigemina. The infundibulum, pendent from the 

 tuber cinereum, leads to the pituitary body. It is patu- 

 lous in the foetus, but exists as a funnel-shaped pit in 

 the adult, 



