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A MANUAL OF ANATOMY. 



The five vesicles furnish the following parts of the adult 

 brain : 



The forebrain gives origin to the cerebrum, corpora 

 striata, olfactory lobes and the lamina terminalis, (the ex- 

 treme anterior part of the interbrain, which lies between 



Diag. 13. A Third Stage in the Development of the Cerebral Vesicles. (Altered 

 from Huxley.) HORIZONTAL ANTEROPOSTERIOR SECTION, "ROOF" OF CEREBRAL 

 VESICLES REMOVED. i, Olfactory bulb, opening into 2, The forebrain. (Cerebrum.) 

 3, Interbrain. (Optic thalamus.) 4, Midbrain. (Corpora quadrigemina.) 5, Hindbrain. 

 (Cerebellum.) 6, Afterbrain. (Medulla.) 7, Pineal gland removed, a, Opening from 

 olfactory bulb into forebrain cavity. The letter lies in the future lateral ventricle, b, 

 Blind pit of the infundibulum. c, Beginning of corpus striatum. d, Beginning of optic 

 thalamus. e, Site of the future foramen of Monro, connecting the cavity of the fore- 

 brain (lateral ventricle) with the cavity of the interbrain (the third ventricle), f, 

 Aqueduct of Sylvius. (Cavity of the midbrain.) g. Fourth ventricle. (Cavity of the 

 hind and afterbrain.) x, Lamina terminalis. 



and connects the forebrain), from which are developed the 

 corpus callosum, septum lucidum, fornix, and anterior 

 commissure. The cavity within the forebrain is the lateral 

 ventricles. 



