534 



THE CEEEBSUM. 



the opposite side to form tlie optic commissure, from the fore part of 

 which the optic nerves proceed. 



Limited behind by these diverging peduncles, and in front by the 

 converging optic tracts, is a lozenge-shaped interval, called the interpe- 

 duncular sjMce, in which are found, in series from behind forwards, the 



Fig. 376. Fig. 376.— View from 



BEFORK OF THE ME- 

 DULLA Oblongata, 

 Pons Varolii, Crura 

 Cerebri, and other, 

 Central Portions op 



THE EnCEPHALON. 



(Allen Thomson.) 



On the riglit side the 

 conviilutions of the cen- 

 tral lobe or island of Reil 

 have been left, together 

 with a small part of the 

 anterior cerebral convolu- 

 tions : on the left side 

 these have been removed 

 by an incision carried 

 between the thalamus 

 02:itieiis and the cerebral 

 hemisphere. 



1', the olfactory tract 

 cut short and lying in its 

 groove between two con- 

 volutions ; II, the left 

 optic nerve in front of 

 the commissure ; 11', the 

 right optic tract ; Th, the 

 cut surface of the left 

 thalamus opticus ; C, the 

 central lobe or island of 

 Keil ; Sy, fissure of 

 Sylvius ; X x , locus 

 perforatus anterior ; e, 

 the external, and i, the 

 internal corpus genicu- 

 latum ; It, the hypophysis 

 cerebri or pituitary body ; 

 tc, tuber cinereum with 

 the infundibulum ; a, one 

 of the corpora albicantia ; 

 P, the cerebral peduncle 

 or crus ; /, the fillet ; 

 III, close to the left 

 oculo-motor nerve ; x , 

 the locus perforatus jios- 

 ticas ; PV, pons Varolii ; 

 V, the greater root of the fifth nerve ; + , the lesser or motor root ; on the right side 

 this + is placed on the Gasserian ganglion, and points to the lesser root, where it proceeds 

 to join the inferior maxillary nerve ; ophthalmic division of the fifth nerve ; 2, superior 

 maxillary division ; 3, inferior maxillary division ; VI, the sixth neiwe ; VII a, the 

 facial ; VII h, the auditory nerve ; VIII, the pneumo-gastric nerve ; VIII a, the glosso- 

 pharyngeal ; VIII b, the spinal accessory nerve ; IX, the hypoglossal nerve ; / /, the floc- 

 culus ; fh, the horizontal fissure of the cerebellum {Ct) ; a m, the amygdala ; 2^ ct, the 

 anterior pyramid ; o, the olivary body ; r, the restiform body ; d, the anterior median 

 fissure of the spinal cord, above which the decussation of the pyramids is represented ; 

 c a, the anterior column ; c I, the lateral column of the spinal cord ; C I, the suboccipital 

 or first cervical nerve. 



i ca 



