ME. J. L. CLAEKE ON THE INTIMATE STEUCTUEE OF THE BEAIN. 
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under or anterior border of the restiform body, they collect into a fusiform or a some- 
what triangular group within a pyriform swelling of the nerve (P'). The inner layer of 
the nerve is whiter and more fibrous than the rest, and is continuous with transverse 
fibres (])') which radiate from the restiform body around which it winds. These 
transverse radiating bundles (y/), which divide the longitudinal fibres of the restiform 
bodies into flattened bands, belong to a system of arciform fibres which sweep round in 
front of the grey tubercle to the antero-lateral nucleus and olivary body. They are seen 
also aty/y?", fig. 10, Plate VIII., and fig. 24, Plate X. 
(39) A few sections higher up in the medulla, on the inner side of the ganglionic 
enlargement of the nerve, are several irregular clusters of fine nerve-cells (Z, fig. 44, 
Plate X.). They are separated from the grey tubercle (e e) only by the arciform fibres, 
just mentioned, which sweep round it from the restiform body, and they receive bands of 
fibres, which, like the upper roots of the glossopharyngeal nerve, arise from the slender 
longitudinal column (n), and proceed outward along the posterior surface of the grey 
tubercle ( e e), in which the more or less circumscribed spaces represent the cut ends of 
the bundles in the descending portion of the sensitive division of the fifth nerve. At U is 
seen the motor nucleus of the same nerve, increased in dimensions and connected by 
fibres with the “fasciculus teres” (see fig. 46). QQ' (fig. 44) are the cut ends of two 
linece transverse, taking an oblique course over the inner auditory nucleus (i) and the 
“ fasciculus teres.” The network of the outer auditory nucleus {do) tapers forward and 
outward, and completely overlays the grey tubercle ( ee ), with which it is moreover 
intimately connected (see fig. 43). The ganglionic enlargement on the auditory nerve is 
seen at P'. 
(40) A little above this level, in transverse sections carried somewhat obliquely upward 
into the fourth ventricle, the anterior division of the auditory nerve comes into view. It 
consists of two portions of unequal size. The smaller portion (P", fig. 45, Plate XII.) 
runs backward along the upper edge of the restiform body ( c ), with an offset from which 
it then crosses transversely over the superior peduncle of the cerebellum to the inferior 
vermiform process. In this course it is accompanied by other fibres, which form with it 
a kind of band of white substance (d 1 , fig. 45, Plate XII.). This figure represents a 
side view of the human pons Varolii and medulla oblongata, c is the restiform body, 
bending backward to form a kind of fan-shaped expansion. The chief portion of it 
enters the lateral lobe of the cerebellum, grasping, as it were, the corpus dentatum ; 
but a smaller portion turns inward, and arching over the superior peduncle of the cere- 
bellum, enters the superior vermiform process, in company with the auditory roots just 
mentioned. This band of white substance (c") is joined by some twisted fibres (d) 
coming from beneath the fillet (f) and the corpora quadrigemina (q 1 ). Anteriorly it 
is continuous with the epithelium on the surface of the superior peduncle. 
(41) The other portion of the anterior division of the auditory nerve (P", fig. 46, Plate 
XII.) is much larger than the one just described. It traverses the medulla as a 
flattened band beneath the restiform body in a direction inward, backward, and a 
