THE NERVOUS SYSTEM IN GENERAL. 



741 



To these two elements is added a large quantity of blood-vessels, which are 

 incomparably more abmidant in the grey than in the white substance. It must 



Fig. 409. 



MULTIPOLAR OR STELLATE GANGLIONIC NERVE-C^-LL, WITH ONE OP ITS PROLONGATIONS 



a, Becoming continuous with the axis-cylinder of a double-coutoured nerve-fibre, 6. 



Fig. 411. 



Fig. 410. 



SEVERAL MULTIPOLAR NERVE-CELLS. 



be added that in the grey substance the chief ele- 

 ments are these ganglionic cells, supported or bound 

 together by neuroglia, distinct from connective tissue. 



In the nerves, the elementary tubes are alone met 

 with ; they are disposed in long bundles, which are 

 collected into successively increasing fasciculi. A 

 cellulo-vascular envelope — the neurilemma (or peri- 

 neurium) — binds all these fasciculi into a single cord, 

 and forms a special sheath around each of them. 

 The details of their organization will be referred to 

 hereafter. 



It is admitted that the ganglionic nerves, or 



PYRAMIDAL CELL OF THE GREY 

 SUBSTANCE OF THE BRAIN 

 CORTEX. 



N, Nucleus; a, a, small ramified 

 protoplasmic prolongations ; 

 c, prolongations of the base 

 of Deiters (bringing the cells 

 into communication with the 

 axis-cylinder of the nerve- 

 fibre). 



