ME. J. L. CLAEKE ON THE INTIMATE STETJCTUEE OF THE BEAIN. 285 
(28) This intimate connexion of the sensory division of the fifth nerve with the vagus 
and glossopharyngeal nerves in the grey tubercle, as well as the connexion, just shown, 
of its motor nucleus with the glossopharyngeal nucleus, with the returning fibres of the 
glossopharyngeal nerve, and with the “ fasciculus teres,” are facts of uncommon interest. 
(29) The longitudinal fibres (YY', fig. 8, Plate VIII.) immediately in front, and on 
the outer side, of the hypoglossal nucleus ( t ') have the same kind of anatomical con- 
nexion with that nucleus as the antero-lateral white columns of the spinal cord have 
with its anterior horn. In longitudinal sections carried through these columns and the 
hypoglossal nucleus the fibres along the border of the nucleus may be seen to enter 
or issue from it, just as the fibres of the antero-lateral columns do along the border 
of the grey substance in the cord. It has been seen that along the line L t, from the 
spinal-accessory nucleus outward, the longitudinal bundles between N and n are sparing 
and wide apart (see n" ! , fig. 27, Plate X.). In front of this line, however, on the outer 
side of the hypoglossal nucleus, and of the root of the hypoglossal nerve, at V', fig. 8, on 
the opposite half the medulla, the longitudinal bundles are numerous and close together, 
but as in the former case, their fibres are finer than those of the white column at the 
surface. The smaller column (V) immediately in front of the hypoglossal nucleus, 
and between the raphe and the origin of the nerve, contains many coarser fibres than 
those just mentioned. Now this column, as far forward at least as the posterior part of 
the olivary body, is the remains of the anterior column of the spinal cord, left on the 
outer side of the decussating fibres of the anterior pyramid, and known as the non- 
decussating portion of that body. It is seen at V in figs. 2, 3, 4, 5 & 6, Plate VIII. 
In fig. 5, Plate VIII. this column on each side is pushed to the back of the pyramid (y), 
and separated from its fellow by the numerous decussating bundles (n") which sweep 
round from the bases of the posterior pyramids and restiform bodies. In fig. 6, Plate 
VIII. the two columns (V) are brought more closely together, more in front of the hypo- 
glossal nuclei ; and the decussating bundles of arciform fibres (which are now wider 
apart), instead of separating them from these nuclei, cross them transversely and then 
run forward between them to the back of the anterior pyramids and lower ends of the 
olivary bodies. In fig. 8, Plate VIII. they have lost their definite outline, being fused 
with other longitudinal fibres at the back of the anterior pyramids, between the decus- 
sating commissure of the olivary bodies ; and they are still closer together, being sepa- 
rated only by the central raphe, and bounded on their outer sides by the • hypoglossal 
nerves. The anterior cornu (f, fig. 4, Plate VIII.) of the spinal cord is in fig. 5 
resolved into network enclosing longitudinal bundles, and blending with the network (s) 
further back, which is left after the lateral columns have crossed over to the anterior 
pyramids (see n, fig. 28, Plate X.). In its place at/'’, fig. 5, Plate VIII. is developed the 
olivary body (W, fig. 6), which is moreover connected with the white substance of the 
anterior column at its surface. After the bundles from the lateral columns have crossed 
over to the anterior pyramids, the central part of each lateral half of the medulla (at the 
letter U, figs. 6, 9 & 10, Plate VIII.) contain, as I have already stated, a multitude of 
