192 
Fig. 5.—Transverse section behind the commissural region. Camera lucida 
drawing x 7, from a section stained with anilin blue-black. 
Fissura hippocampi. 
Hippocampus (the letter points to the fascia dentata). 
Fimbria. 
Corona radiata. 
Nucleus caudatus. 
Nucleus lenticularis. 
Capsula interna. 
Nucleus amygdale. 
Fig. 6.—Transverse section hippocampus. Notoryctes. 
Fig. 7.—Transverse section hippocampus. Perameles. 
Fig. 8.—Transverse section hippocampus. Ornithorhynchus. 
Fig. 9.—Transverse section hippocampus. Macropus. 
Figures 6-9 are drawn to different scales, but are all taken from correspond- 
alv. 
te: 
h.f. 
f.d. 
Ji 
C. 
Tr. 
ing regions. 
Alveus. 
Subiculum cornu Ammonis. 
Fissura hippocampi. 
Fascia dentata. 
Fimbria. 
Corona radiata. 
Fig. 10.—Sagittal section through the median hemisphere wall in the commis- 
sural region. Perameles. Drawn by camera lucida. Weigert-Pal 
stain. x 5. 
The appearance in Noforyctes would be almost exactly identical with 
this. 
a.C. 
ps.d. 
spl. 
cm 
a.f. 
R. 
A: 
iB. 
Commissura anterior. 
Commissura hippocampi—crus dorsale. 
. Crus ventrale. 
‘¢Splenium commissure hippocampi” (mihi). 
**Septum lucidum” (lamina terminalis). 
Columna fornicis. 
Riechbundel des cornu Ammonis (Zuckerkandl) lying in 
the precommissural area of the median hemisphere wall. 
Fibres of the Riechbunde passing directly to the hippocam- 
pus without passing through the fornix. 
Fibres directed backwards below a.c. to the floor of the 
thalamencephalan. 
Fibres directed forwards to the olfactory bulb and base of 
brain (tuberculum olfactorium and lower part of pre- 
commissural area). 
Fig. 11.—Horizontal section through the olfactory bulb and peduncle. 
Notoryctes. x about 8. 
Pars olfactoria commissure anterioris. 
. ‘Olfactory peduncular projection bundle.” 
. Radiatio olfactoria externa. 
Radiatio olfactoria interna, its fibres extending into the 
precommissural area (p.a. ). 
Ventriculum olfactorium. 
Layer of glomeruli and nerve fibres. 
Layer of mitral cells. 
Layer of diffuse nerve fibres. 
Layer of compact nerve fibres. 
