MR. J. L. CLARKE ON THE INTIMATE STRUCTURE OF THE BRAIN. 
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upper and lower ends of the longitudinal section, after it was removed. In 
figs. 58 & 59, the upper lines of section correspond : — F is the raphe immedi- 
ately below the median furrow of the ventricle ; V, the white column between 
the raphe and the entrance of the abducens (V') into the nucleus (Q") ; d is the 
base of the grey tubercle ; do, the outer auditory nucleus. The lower line of 
fig. 58 corresponds to the upper line of the transverse section, fig. 60, in which 
J is the anterior portion of the hypoglossal nucleus; V the white column 
between it and the raphe ; O", the white olivary column lying between it and 
the vagus nucleus (H); n, the slender longitudinal column of the vagus; 
do', the lower end of the outer auditory nucleus, formed by the grey substance 
of the restiform body and posterior pyramid. The white column, Y, (fig. 59), 
between the raphe (F) and the entrance of the abducens nerve into the nucleus 
(Q") is continuous in fig. 60 with the white column (V) between the hypoglossal 
nucleus (J) and the raphe. 
Fig. 61. Transverse section of part of the left lateral half of the medulla oblongata of 
the Rabbit, through the trapezium: — e, grey tubercle; d', descending root 
of the trigeminus; g", facial nerve; p',p", arciform fibres running forward 
and inward through the trapezium in front of the superior olivary body, s". 
Fig. 62. Transverse section through the whole left lateral half of the medulla at the 
level of the facial and abducens nerves, from the Orang Outang : — Q", com- 
mon nucleus of facial and abducens nerves ; T", descending portion of loop of 
facial. Transverse fibres of trapezium (p") more concealed by the enlarged 
pyramid ( y ). 
Fig. 63. A similar section from Man. Here the transverse fibres of the trapezium' (p") 
are completely enclosed and concealed by the anterior pyramid and pons 
Varolii. 
Fig. 64, A. Atrophied nerve-cells from the olivary bodies, in a case of paralysis ; magni- 
fied 350 diameters. 
Fig. 64, B. Cells from a healthy olivary body; magnified 350 diameters. 
Fig. 65. Transverse section through the fourth ventricle on a level with the facial and 
abducens nerves, from a child : the letters indicate the same parts as in other 
figures. 
