THE FOREBRAIN OF THE ALLIGATOR 343 
small celled area of this description and is comparable with the 
area termed nucleus caudatus in turtles. 4. Between the 
dorso-lateral area and the ventro-lateral, large celled area, in 
the anterior end of the brain, there is an intermedio-lateral area 
which at first is closely tied up with the anterior part of the nu- 
cleus of the lateral olfactory tract, but later becomes continuous 
with the dorso-lateral area and probably is a part of that area. 5. 
The nucleus of the lateral olfactory tract is situated in the later- 
al part of the hemisphere, ventral to the dorso-lateral area and 
dorso-lateral and lateral to the ventro-lateral areas (the corpus 
striatum of Johnston’s description). It lies in intimate relation 
with the intermedio-lateral area and is apparently continuous 
with it. Dorsalward it is at first clearly distinct from the dorso- 
lateral area but finally merges with it. Behind the level of the 
tuberculum olfactorium the more ventral part of the nucleus of 
the lateral olfactory tract becomes continuous with the nucleus 
of the diagonal band of Broca and then swings farther ventral- 
ward until it occupies the greater portion of the ventral region 
of the hemisphere internal to the cortex of the pyriform lobe 
and in close relationship with it. The nucleus of the lateral 
olfactory tract of the alligator, as the name is used in this paper, 
includes both the nucleus of that name and a small celled, ven- 
tral portion of the pyriform lobe as described in turtles. 6. In 
close relation with the nucleus of the lateral olfactory tract in 
the ventro-medial angle of the posterior half of the hemisphere 
is a nucleus to which the name of the ventro-medial nucleus 
has been given. This nucleus (figs. 18 to 21) gives rise to the 
projection tract of Cajal, and corresponds to the medial large 
celled nucleus described in turtles (Johnston,’15). 7. The outer 
ventro-lateral and ventral portions of this lateral wall are occu- 
pied farther cephalad by the cells of the tuberculum olfactorium 
and behind the level of that cell mass (8) by a part of the nu- 
cleus of the diagonal band of Broca. These two centers have 
been described previously. (For a more complete discussion 
of the extent, relations, and fiber connections of these nuclei 
of the lateral wall see the special headings.) 
