646 



MAMMALIA 



[CH. 



of the first visceral arch, as it should be if it represents the 

 quadrate. 



The chief peculiarity of the brain as compared with Reptiles 

 is the greater development of the cerebral hemispheres, in 



FIG. 319. Brain of Eabbit, Lepus cuniculus x 2. 



A. Dorsal aspect. B. Ventral aspect. 



1. Olfactory lobe. 2. Pituitary body. 3. Crura cerebri. 4. Pineal 

 gland. 5. Anterior pair of corpora quadrigemina. 6. Pons Varolii. 

 7. Cerebellum. 8. Lateral lobe of cerebellum. 9. Floccular lobe of 

 cerebellum. 10. Medulla oblongata. 11. Sylvian fissure separating 

 the frontal lobe 12 from the temporal lobe behind. i. Origin of first 



or olfactory nerves. n. Optic or second nerves arising from the optic 



chiasma. in. Third or motor oculi nerve. iv. Fourth or patheticus 

 nerve. v. Fifth or trigeminal nerve. vi. Sixth or abducens nerve. 

 vn. Seventh or facial nerve. vni. Eighth or auditory nerve, 



ix. Ninth or glossopharyngeal nerve. x. Tenth or vagus nerve, 



xi. Eleventh or spinal accessory nerve. xn. Twelfth or hypoglossal 



nerve. 



