ANATOMY IN A NUTSHELL. 



437 



Every sensory point of the body is connected to every motor point by a re- 

 flex pathway, and all nerve impulses conform to the reflex type. 



A reflex impulse may pass over many different paths between any given 



sensory point and motor point. (Plate CCXXXII) show- both afferent and 

 efferent pathways. 



The brain is a collection of gray ganglia connected by white commissures. 

 (Xote). The middle commissure is gray, but it is not a commissure in the true 

 sense because it has not fibers hi it. 



When we can name and define the commissures of the brain and give the 

 boundaries of all the ventricles and describe each structure which helps to 

 make these boundaries, then we understand something of the brain. 



LESSOX CXXXI. 



The Transverse Commisures are : 



1. Anterior commissure. See page 347 



2. Middle commissure. See page 348 



3. Posterior commissure. See page 348 



4. Optic commissure. See page 366 



5. Corpus callosus. See page 350 



6. Pons varolii. See page 362 



7. Fornix, also longitudinal. Page 348 



8. Sup. or ant. medullary velum 

 (valve of Yieussens.) 



9. Inf. or post, medullary velum 



The Longitudinal commissures are: 



1. Olfactory tracts. See page 365 



2. Tsenia Semicircularis. See page 356 



3. Crura cerebri. See page 363 



4. Processus-e-cerebello-ad-testes. 

 page 354 



5. Peduncles of pineal glad. 



6. Fornix. See page 348 



7. Gyrus Fornieatus. 



8. Lamina cmerea. See page 345 



9. Infundibulum. 



10. Fasciculus uniformis. 



See 



LESSON CXXXII. 

 Third Ventricle. 



ROOF. 



1. Corpus callosum. See page 350 



2. Fornix. See page 348 



3. Velum interpositum (Tela choroidea 

 superior). See page 351 



4. Epithelium. 



floor. 



1. Tegmental portion of the diverg- 

 ing crura cerebri. See page 363 



2. Posterior perforated spare 



3. Corpora albican i in. See pa.ue 349 



4. Tuber cinereum. 



5. Infundibulum. 



6. Lamina cinerea (anterior wall). 



WTKRlnR BORDER. 



1. Anterior commissure. See page 347 



2. Anterior pillars of fornix. Page 349 



3. Foramen of Monro. Seepage ".11 



P< istkriok BORDER. 



1. Posterior commissure. Page 348 



2. Aquedud of Sylvius. Page 341 



3. Epithelium from pineal body 



to velum interpositum (tela choroi- 

 dea superior). 



BIDES. 



1 . ( tptic thalamus. See page :, 



