414 “J. B. JOHNSTON 
Where the thin layer of small cells forms the boundary of the 
striatal area it covers in the large-celled lateral nucleus of the 
corpus striatum (nucleus lentiformis) (fig. 16). In transverse 
sections the nucleus lentiformis is followed caudad for some 
distance beyond this, always traversed by bundles of crucial 
fibers which are bending up into the pallium and the dorsal 
ventricular ridge. The nucleus lentiformis gradually grows 
smaller and is replaced by the small-celled nucleus which grows 
thicker caudally and enters into close relations with the caudate 
nucleus. Indeed, in its rostral portion the entire amygdaloid 
eminence is filled with small cells, the ventricular portion being 
the caudate nucleus, the superficial portion being the enlarged 
continuation of the nucleus of the lateral olfactory tract (fig. 17). 
Relations of the caudate nucleus. It has been stated that the 
caudate ends about opposite the end of the middle ventricular 
eroove and is bounded by the branch of that groove which 
bends down into the temporal horn of the ventricle. Here the 
caudate merges with the nucleus of the lateral olfactory tract in 
‘a small-celled mass which constitutes the chief part of the amyg- 
daloid complex. In the lizards this mass, or the caudate part of 
it, is greatly enlarged and forms a prominent lobe or ridge in the 
ventricle. C. L. Herrick showed that this was an important 
olfactory center and it is this lobe which was first called epistri- 
atum by Edinger. It was this body whose relations very natu- 
rally suggested to Kappers (’08) that the epistriatum of lower 
vertebrates formed or entered into the amygdaloid complex of 
mammals. In the turtle this body is simply a part of the amyg- 
daloid complex without hypertrophy. However, if all the other 
structures to which the term epistriatum has been applied were 
to be gathered into it, the amygdaloid complex would be a 
veritable museum! 
The caudate nucleus at its rostral end is closely related to the 
olfactory tubercle and parolfactory area and receives fibers 
from the medial olfactory tract. At its caudal end it enters 
into close relations with the nucleus of the lateral olfactory tract 
and helps to form the olfactory part of the amygdaloid complex. 
