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ANATOMY AND PHYSIOLOGY OF THE BRAIN. 



Table indicating the Weight of the Encephalon and Spinal Cord, as com- 

 pared with that of the Body. (Colin.) 



That portion of the cerebro-spinal axis contained within 

 the cranium has been subdivided into four portions, namely, 

 the oblong medulla, which is continuous with the spinal 

 cord ; the brain (cerebrum), which occupies the greater part 

 of the cranial cavity, and is placed anteriorly; the little 

 brain (cerebellum), placed behind the brain proper and 

 above the oblong medulla; and, lastly, the pons Varolii, 

 or tuber annulare, a ring-like eminence at the anterior part 

 of the medulla, and occupying the point of union of the 

 three above-mentioned parts. 



The whole mass consists of a series of ganglia and nerve- 

 fibres, the former being sometimes connected individually 

 with others in adjacent parts of the encephalon, so that a 

 short outline of its anatomy will be needful. 



The oblong medulla presents an external appearance 

 somewhat similar to that of the spinal cord ; it is, however, 



