96 MR. OWEN ON THE STRUCTURE OF THE BRAIN IN MARSUPIAL ANIMALS. 
y. The anterior commissure. 
%. Soft commissure. 
m. Hippocampal commissure. 
cc. The third ventricle. 
(3. The iter ad infundibulum. 
7. The foramen Monroianum. 
The iter ad quartum ventriculum. 
s. The val vula Vieussenii. 
The fold of the valve corresponding to the posterior commissure. 
