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PLATE X.
THE SKATE.
(RAIA BATIS.)
FIGURE I.
THE DORSAL ASPECT OF THE BRAIN AND SPINAL CHORD.
- a. Anterior lobes of the brain.
- b. Pedicles of the anterior lobes, corresponding with the crura of the brain.
- c. Optic lobes.
- d. Cerebellum; its middle portion is smooth, but that on each side is convoluted.
- e. Nose.
- 1. Olfactory nerve; it arises, or is continued from the anterior lobe; it passes out of the cavity of the skull, and forms a long ganglion over the nose, which gives off numerous branches to pass through holes in the membrane, corresponding with the cribriform plate of the ethmoid bone, to the membranous plaits or folds of the nose.
- 2. Optic nerve.
- 3. Third nerve passing to all the muscles of the eye, except the superior oblique and
the abductor.
- 4. Fourth or pathetic nerve: it arises just beyond the posterior point of the optic lobe.
