PLATE 2 
A series of camera tracings of transverse sections of the head of Lepidosteus 
of 10 mm. length. The numbers following the number of the section indicate 
the level at which the section falls, as indicated on the scale over fig. 1. The 
sections are slightly diagonal, the right side of figure being further anterior. 
Fig. 2 is taken at the level of the olfactory capsule and nerve. 
Fig. 3 passes through the anterior portion of the qptic vesicle and the epiphysis 
and dorsal sac. 
Fig. 4 lies just posterior to the lens and passes through the anterior end of the 
profundus ganglion. 
Fig. 5 passes through the third nerve, on right side of figure, and the posterior 
end of the profundus ganglion. The anterior end of the hypophysis is cut in this 
section. 
Fig. 6 passes through the posterior end of the Gasserian on right side of figure 
and the anterior end of the lateral lobes of the medulla. 
Fig. 7 passes through the root of the Gasserian ganglion on right side and the 
posterior end of the mesencephalon. 
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