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direct contact with the giant cells and the rest of the medulla through 
‘the central area, there appears a pre-central (oberer Markballen) 
area, described in part by Samassa (Diagrams 5, 6; Fig. 8, 9, 10, 11). 
The antero-posterior commissures diverge anteriorly and form 
the lateral boundaries of the small and medium-sized cell group. 
After the passage of the oculomotor nerve bundles there is a 
single lateral area and the pre-central area also disappears. 
A post-lateral, medullary area appears in each of the posterior, 
large-cell groups and the posterior area is divided by entering nerve 
fibres (Diagram 7; Fig. 12, 13). 
The medullary area is united with that of the optic ganglion, 
but only after the entrance of the optic nerve fibres (Diagrams 4, 5, 6; 
Fig. 11). 
Ventrally, the lateral and central areas disappear, the post-lateral 
areas gradually increase and finally unite (Riechcentrum) in the median 
line, and two post-central areas are noted in the post-lateral 
commissure (Diagrams 8, 9; Fig. 13, 14, 15). The post-central 
areas unite (Centralkérper) and disappear as the ventral cortical wall 
is approached but the post-lateral areas are united into a common 
area, only to be divided again by a ventral antero-posterior 
commissure (Diagrams 9, 10; Fig. 16, 17). 
The medulla and commissures stain dark purplish-red with gold 
chloride. 
Nerves. The oesophageal nerves generally unite on entering the 
brain and pass partly between and partly through two groups of large 
nerve cells (Diagrams 8, 9; Fig. 14, 15, 16). Samassa holds that 
they pass from the ganglion cells and not from the Punktsubstanz. 
This I think is incorrect. It is rare for the cells to be directed 
toward the nerves; the great majority are directed anteriorly and 
are lateral to the entering nerve bundles. Most sections show that 
the nerves are distinct at their origin, although WEISMANN states that 
they are only paired at some distance from the brain. Most of the 
fibres pass through the common post-lateral medulla to the post-lateral 
commissure and from here are distributed to various parts of the 
brain. 
The antennal nerves enter the common post-lateral medulla laterally 
— the fibres being lost in this Punktsubstanz and the commissure. 
The oculomotor nerves pass from their superficial origin backward 
in the lateral areas. They join the median antero-posterior commissures 
laterally opposite the central area and can not be traced farther. They 
do not, apparently, become connected with the central medulla, 
