284 



BIOLOGICAL PHYSICS 



" nervous system " itself, may be regarded, as necessi- 

 tating, and forming another and distinct circulation, or 

 series of circulations, a large part of which, the cerebro- 

 spinal, has been already described. Thus, the neuroglia, 

 which is partly granular, and partly amorphous, inter- 



FlG. 117. THE CRANIUM OPENED TO SHOW THE FALX OF THE CEREBRUM 

 AND TENTOR1UM OF THE CEREBELLUM, AND THE PLACES OF EXIT 

 OF THE CRANIAL NERVES. ^. 



i, falx ; 2, superior longitudinal sinus ; 3, concave border of the falx ; 4, inferior 

 longitudinal sinus ; 5, base of the falx ; 6, straight sinus ; 7, anterior part of the 

 falx ; 8, right side of the tentorium cerebelli, seen from below ; 9, lateral sinus ; 

 ip, superior petrosal sinus; n, inferior petrosal sinus; 12, posterior occipital 

 sinus; 13, falx cerebelli; 14, 15, 16, 17, 18, second, third, fourth, fifth, and sixth 

 cranial nerves; 19, seventh and eighth nerves; 20, ninth, tenth, and eleventh 

 nerves ; 21, twelfth nerve ; 22, 23, first and second cervical nerves ; 24, upper 

 end of the ligamentum denticulatum. 



penetrated, and supported, by a fibro-cellular meshwork 

 of very fine texture (Fig. 119) is at once, the physical 

 foundation, or basis, on which the component neurons of 

 the systemic nervous (see Fig. 1 1 7) system rest, from which 

 they grow, as plants do from the soil, from which they 

 extract their nutriment, and to the support, and integrity, 

 of which, all the organs, and structures, of the body, 



