566 



NERVOUS SYSTEM 



relations of which are not understood ; still, there are certain parts, which 

 will be referred to by name, a general knowledge of the arrangement of 

 which is necessary. The general relations of these parts are shown in 

 Fig. 134, slightly reduced and modified, from Harrison Allen, which 

 represents a vertical longitudinal section of the brain in the median 

 line. 



As bearing on certain points in the physiology of the brain, it is 

 important to note the weight of the entire encephalon and of its great 

 divisions. 



ANTERIOR CPUS 

 OF FORNIX 



!jL L & /FISSURE OFROLANDO 



PITUITARY BODY 



FORAMEN OFMONRO 

 MIDDLE COMMISSURE; 



OPTIC THALAMUS 



3 NERVE 

 AQUEDUCT OFSYLVIUS. 



PINEAL GLAND.' 

 CORPORA QUADRIGEMINA' 



TRANSVERSE 

 FISSURE 



VALVE 

 OF VIEUSSENS 



4" VENTRICLE 



Fig. 134. View of the structures displayed on the right side of a median longitudinal section of the 



brain semidiagrammatic. 



Weights of the Encephalon and of Certain of its Parts. Most of the 

 tables of weights of the healthy adult brain of the Caucasian, compiled 

 by different writers, give essentially the same figures, the differences 

 amounting to only one or two ounces (28.3 or 56.7 grams) for the entire 

 encephalon. The average weight given by Quain, combining the tables 

 of Sims, Clendinning and Reid, is 49^ ounces (1408.3 grams) for the 

 male, and 44 ounces (1247.4 grams) for the female. The number of 

 male brains weighed was 278, and of female brains, 191. In males the 

 minimum weight was 34 ounces (963.9 grams), and the maximum, 65 

 ounces (1842.7 grams). In 170 cases out of the 278, the weights ranged 

 between 46 and 53 ounces (1304.1 and 1502.5 grams), which may be 



