680 



MANUAL OF PHYSIOLOGY. 



cavity of the middle cerebral hemisphere, and in front it commu- 



FIG. 268. 



Diagram of the cerebral vesicles of the brain of a chick at the second day. 

 (Cadiat.) 1, 2, 3, Cerebral vesicles. 0. Optic vesicles. 



nicates with the hollow rudiments of the cerebral hemispheres, 



FIG. 



Diagram of a vertical longitudinal section of the developing brain of a 

 vertebrate animal, showing the relation of the three cerebral vesicles to the 

 different parts of the adult brain. (Huxley.) O//. Olfactory lobes. P.M. 

 Foramen of Monro. C.S. Corpus striatum. Th. Optic thalamus. Pn. Pineal 

 gland. M.b. Mid-brain. 06. Cerebellum. M.O. Medulla oblongata. Hmp. 

 Central hemispheres. ThE. Thalamencephalon. Py. Pituitary body. C.Q. 

 Corpora quadrigemina. C.C. Crura cerebri. P. V. Pons Varolii. /. XII. 

 Regions from which spring the cranial nerves. 1. Olfactory ventricle. 2. 

 Lateral ventricle. 3. Hind ventricle. 4. Fourth ventricle. 



and eventually it becomes the cavity of the third ventricle. The 



