THE BRAIN. 123 



gi/en to the regions between the calcarine, parieto-occipital, and calloso-marginal 

 fissures, the last-named locality lying in front of the last-named fissure. 



Name the Points in view on the Inferior Surface of the Brain. From 



before backwards, excluding the cranial nerves, are the following: 



Longitudinal Fissure, its anterior portion. 



Corpus Callosum, the great transverse commissure of the brain. 



Lamina Cinerea, a thin, gray layer, beneath the optic tracts. 



Fissure of Sylvius, between the anterior and temporo-sphenoidal lobes. 



Anterior Perforated Space, for vessels to the corpora striata. 



Optic Commissure, formed by the junction of the optic tracts. 



Tuber Cinereum, a gray lamina behind the optic commissure, forming part 

 of the floor of the 3d ventricle. 



Infundibulum, a hollow process, connecting the pituitary cavity with the 3d 

 ventricle in the foetus. 



Pituitary Body, a vascular bi-lobed body, of glandular structure, projects 

 from the infundibulum into the sella turcica of the sphenoid. 



Corpora Albicantia, two round, white eminences, united together ; they are 

 the anterior crura of the fornix folded on themselves. 



Posterior Perforated Space (Pons Tarini}, for vessels to the optic thalami. 



Crura Cerebri, or cerebral peduncles, connect the cerebrum with the cere- 

 bellum, spinal cord, and medulla oblongata ; containing the fibres passing 

 to the basal ganglia. They, with the optic tracts, form the boundaries of 

 the Inter-peduncular Space. 



Pans Varolii, to be described separately. [See page 127.] 



What Ganglia are comprised in the Brain ? Besides the gray matter of 

 the cerebral hemispheres, of the cerebellum, and of the medulla oblongata, 

 there are the following at the base of the brain : 



Olfactory Bulbs. Optic Thalami. Tuber Annulare. 



Corpora Striata. Tubercula Quadrigemina. 



Describe the Basal Ganglia. They are as follows, viz. 

 Olfactory Bulbs are the ganglia of the sense of smell, lie one on each side of 



the median line, upon the cribriform plate of the ethmoid, and are connected 



with the hemispheres by the Olfactory Tracts. 

 Corpora Striata, the motor ganglia, are situated in the floor of the lateral 



ventricles, and therefore within the hemispheres. Each corpus striatum 



has a 



Caudate Nucleus, the intraventricular part. 

 Lenticular Nucleus, the extraventricular part. 

 Internal Capsule, divides these two parts. 

 Optic Thalami, the sensoiy ganglia, are in the floor of the lateral ventricles, 



