90 OSBORN. [Vot. II. 
EXPLANATION OF PLATES IV.-VI. 
INDEX LETTERS TO ALL FIGURES. 
The Encephalic Segments. — Rh, rhinencephalon, olfactory lobes. Pr, prosence- 
phalon, cerebral hemispheres. Dz, diencephalon, optic thalami. Ze, mesencepha- 
lon, optic lobes. J/¢, metencephalon, medulla oblongata. 
Ventricles. — a, aula, ventriculus communis. /rc, prosoceele. Z, porta, foramen 
of Monro. a, diaccele. msc, mesoccele. wfc, metaccele. zx/f, infundibulum. 
The Commissures. — cto, commissure of the tectum opticum. ca@/, corpus callosum; 
cal', posterior division of same, (?comm. cornu ammonis). 2c, inferior infundibu- 
lar commissure. cs, posterior commissure. rcs, anterior commissure. scm, superior 
infundibular. scs, superior commissure. 
Cranial Nerves. —I1.-IV., as usual. V./, opthalmic; V.!, superior maxillary; 
V.'"", inferior maxillary, divisions of the Trigeminal. VII, Facial, upper bun- 
dle, joining the Gasserian Ganglion; VII.", lower bundle joining the Auditory and 
sending off the 2. mentalis and R. jugularis. VIII., Auditory. IX., Glosso- 
pharyngeus. X., Vagus. XI. (XII.), Hypoglossal. 
The Encephalic Nerve Tracts. —bpt, basal prosencephalic tract. 6/f, same. 
chit, cerebellar tract entering optic lobes. cé/¢, cerebellar tract from medulla oblon- 
gata. dst, sensory (?) tract to optic thalamus. ds¢’, sensory tract from optic thala- 
mus to hemispheres. /<, fasciculus communis. /%, fasciculus solitarius. 7¢, tract 
from infundibular lobes to hemispheres. st, sensory (?) tract to mesencephalon. 
mst!, sensory tract from mesencephalon to hemispheres. md, Meynert’s bundle. 
PF, posterior longitudinal fasciculus. 
Cranial Nerve Tracts. Trigeminus.—s5?, the ascending tract. 5 4%, the 
ascending tract reinforced by the tract from the great motor nucleus. 5 ¢%, the sen- 
sory tract. 5 ¢4, the descending (mesencephalic) tract. 5 75, the encephalic tract. 
Facialis. — 7 tl, lower, motor (?) tract. 7 ¢#, upper, sensory tract. 7 ?, ence- 
phalic tract. 
Acusticus. —§8 ¢, tract from the pale nucleus, and special sensory nucleus. 8?, 
cerebellar tract. 
Glossopharyngeus. — 9 ¢, sensory tract. 
The Encephalic and Cranial Nerve Nuclei. — 3, 3 ', upper and lower Oculo- 
motor nuclei. 4, Trochlearis, motor nucleus. 557, dorsal sensory nucleus of 
Trigeminus. 5 #7, ventral motor ditto. 5, mesencephalic nucleus of Trigeminus. 
6, Abducens nucleus. 75”, and mm, dorsal sensory and lateral motor nuclei of 
Facialis. 8, Auditory nucleus of pale ganglion cells. 8s, Auditory nucleus of 
small sensory cells. 9 mm, lateral motor nucleus ot Glossopharyngeus. 9 sz, dorsal 
sensory nucleus of same. 9, ventral motor nucleus of same. 10, ventral motor 
nucleus of Vagus. cé/.m, cerebellar nucleus. cs, corpus striatum. dn, superior 
diencephalic nucleus. dz’, inferior diencephalic nucleus. fev, nucleus of fasciculus 
communis. gc, nucleus of large ganglion cells opposite Auditory root. gh, ganglion 
habenule. 7, interpeduncular ganglion. mc, nucleus centralis. #2, nucleus mag: 
nus. #/, pale nucleus, 
