410 



THE NERVOUS SYSTEM. 



matter of these two ganglia, while others start afresh from 

 them to enter the cerebral hemispheres ; or whether some of 

 the fibres of the crura pass through them, while only a portion 



FIG. 145. 



Shows the under surface or base of the encephalon freed from its membranes A, 

 anterior, B, middle, and c, posterior lobe of cerebrum. a. The fore part of the great 

 longitudinal fissure. 6. Notch between hemispheres of the cerebellum, c. Optic 

 commissure, d. Left peduncle of cerebrum, e. Posterior perforated space, e to i. 

 Interpeduncular space. //'. Convolution of Sylvian fissure, h. Termination of 

 gyrus fornicatus behind the Sylvian fissure, i. Infundibulum. I. Right middle 

 crus or peduncle of cerebellum, m m. Hemispheres of cerebellum, n. Corpora 

 albicantia. o. Pons varolii, continuous at each side with middle crura of cerebel- 

 lum, p. Anterior perforated space, q. Horizontal fissure of cerebellum, r. Tuber 

 cinereum. s s'. Sylvian fissure, t. Left peduncle or crus of cerebrum, u u. Optic 

 tracts, v. Medulla oblougata. x. Marginal convolution of the longitudinal fissure. 

 1 to 9 indicate the several pairs of cerebral nerves, numbered according to the usual 

 notation, viz. 1. Olfactory nerve. 2. Optic. 3. Motor nerve of eye. 4. Pathetic. 

 5. Trifacial. 6. Abducent nerve of eye. 7. Auditory, and 7'. Facial. 8. Glosso- 

 pharyngeal, 8'. Vagus, and 8". Spinal accessory nerve. 



can be strictly said to have their termination there, must re- 

 main at present undecided, the difficulties in the way of solv- 

 ing such an anatomical doubt being at present insuperable. 



