602 



NERVOUS SYSTEM. 



this work, as there are many anatomical parts, the exact physiological rela- 

 tions 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. 219, 

 slightly reduced and modified, from Harrison Allen, which represents a ver- 

 tical longitudinal section of the brain, in the median line. 



As bearing upon certain points in the physiology of the brain, it is im- 

 portant to note the weight of the entire encephalon and of its great divisions. 



p A RIETA 



FISSURE OFROLANOO 



CALIOSO-MARGINAL SULCUS 



SEPTUM v 



LUC I DUM^l 



ANTERIOR CRUSjf 

 Or FORNIX 



PITUITARY BODY 



FORAMEN OFMONRO 

 MIDDLE COMMISSURE 



PINEAL GLAND. 

 CORPORA QUADRIGEMINA 1 



4 T " VENTRICLE 



FIG. 219. View of the structures displayed upon the right side of a median longitudinal section of the 



brain semi-diagrammatic. 



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

 tables of weights of the healthy adult brain of the Caucasian, given by differ- 

 ent observers, give essentially the same figures, the differences amounting 

 to only one or two ounces (28*3 or 56*7 grammes) for the entire encepha- 

 lon. The average weight given by Quain, combining the tables of Sims, 

 Clendinning, and Reid, is 49 ounces (1,408-3 grammes) for the male, and 44 

 ounces (1,247'4 grammes) 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 grammes), and the maximum, 65 ounces (1,842*7 

 grammes). In 170 cases out of the 278, the weights ranged between 46 and 

 53 ounces (1,304-1 and 1,502-5 grammes), which may be taken as the average 

 limits. In females the minimum was 31 ounces (878*8 grammes), and 

 the maximum, 56 ounces (1,587*6 grammes). In 125 cases out of the 191, 

 the weights ranged between 41 and 47 ounces (1,162-3 and 1,332*4 grammes). 



Quain assumed, from various researches, that in new-born infants, the 



