404 J. B. JOHNSTON 
fascicles of nerve fibers are found running to or from them, con- 
stitute negative evidence as to their nervous function. At the 
same time, nerve cells are often found closely related to or im- 
bedded in the ependyma and further study will be necessary 
to determine the origin, character and significance of these 
structures. 
THE LENTIFORM NUCLEUS 
At its rostral end this nucleus appears simply as scattered large 
cells, outside of the small-celled caudate, among which fascicles 
rise from the crus to the pallial thickening in the rostral part of - 
the roof. Beneath the rostral end of the dorsal ridge this nucleus 
has grown to a large body in the lateral wall and has reached 
the ventricle (figs. 22; 23). From this point caudad a peculiar 
band of thickened ependyma covers the ventricular surface of 
this nucleus (figs. 15 to 22,36). This thick band extends some 
distance below the middle ventricular groove and bends round 
that groove into its dorsal wall. While the ependyma elsewhere 
in the lateral ventricle has from one to three rows of nuclei, this 
band consists of very tall cells and presents as many as seven to 
nine rows of nuclei. The peripheral processes of these cells are 
strong and give a prominent striation to the adjoining nucleus 
(figs. 36, 37). The curved course taken by these processes which 
come from the dorsal wall of the middle groove (fig. 37) shows 
that the groove was formed within the ependymal band and near 
the border of this nucleus. It also shows how the groove has 
been formed during the development of the individual by the 
pushing uf of the dorsal ridge which forced this border of the 
nucleus to be bent over. This thickened ependyma extends 
right back into the dorsal branch of the middle ventricular groove, 
where it quickly disappears. Throughout its length this thick- 
ened band of ependyma covers a nucleus whose cells are dis- 
tinctly larger and usually much more numerous than those of the 
adjoining caudate. : 
In the striatal area this nucleus makes up the whole thickness 
of the wall and is traversed by the fascicles of the crus as above 
noted. ‘Toward the caudal border of the striatal depression 
