mammal consists of a linear arrangement of three hollow vesicles
(Figure 5, Sheet VIII., 1, 2, and 3), which are the fore-, mid-, and
hind-brain respectively. The cavities in these in these vesicles are
continuous with a hollow running through the spinal cord. On the
dorsal side of the fore-brain is a structure to be dealt with more fully
later, the pineal gland (p.g.), while on its under surface is the
pituitary body (pt.).