308 Anatomy of the Floor of the Fourth Ventricle 
tion between the dorsal nucleus of the vestibularis and the nucleus inter- 
calatus. This is indicated in text fig. 2, which represents a neuroglia 
Nucl vestibularis 
Stria medull 
Nucl. intercalatus 
Fasc. solitar. Nucl. funic. teretis 
Text Fie. 2. Neuroglia preparation made in the region corresponding to fig. 6, in 
Plate IV. The magnification is the same as text fig. 1. 
fibre preparation taken from the region under consideration. In sec- 
tions from other specimens we have observed a distinct notch in the 
floor at the point indicated in text fig. 2 by a cross. These would cor- 
respond to brains with a well marked lateral furrow. 
As bearing on this subject, I may further mention a case, reported 
by Neubiirger and Edinger (Berliner klin. Wochenschr., 1898, No. 4), 
in which there was a congenital absence of one-half of the cerebellum. 
On the abnormal side the vago-glossopharyngeal and vestibular nuclei 
were found to be devoid of the network of fine fibres, which presumably 
forms the origin of their central cerebellar sensory tract. The nucleus 
intercalatus was not described. I have recently, however, had the 
opportunity of examining the preparations from this case, and find that 
the so-called nucleus intercalatus, in its greater part, is normal in 
appearance, and equally rich in fibre network on both sides. It thus 
stands out separated in sharp contrast from the pale and transparent 
field occupied by the vagus and vestibular nuclei. 
In fig. 6, overlying laterally the restiform body, there is seen a nuclear 
structure in the substance of the tela choroidea inferior. This can be 
traced through the sections between 5 and 6 as a thin nuclear layer or 
lamella which extends caudally from the nucleus cochlearis, and later- 
ally from the nucleus vestibularis. Whether it is a part of either or 
both of these we were unable to satisfactorily make out. In Plate IT 
it is represented as belonging to the cochlear area. The cochlear nucleus 
proper does not make its appearance until we reach the sections lying 
between figs. 6 and 7. 
