CHAP. VIII.] 



NERVES. 



215 



Fig. 



In most situations where vesicular matter is found in the nervous 

 centres, tubular fibres of small though variable size mingle with its 

 elements in greater or less 

 number, and in some places 

 both varieties of fibre are 

 found (figs. 57 & 58). To de- 

 termine the precise connex- 

 ion which these respective 

 elementary parts form with 

 each other is a problem of 

 the deepest interest. No 

 more, however, can be said 

 respecting it at present, 

 than that the relation of 

 nerve- fibres to nerve-vesicles 

 in the centres is most inti- 

 mate, and that the latter are 



nn4- ^"k '4-1^^ 4- A - Blending of the vesicular and fibrous nervous matter 



larely met With WlthOUt One in the dentate body of the cerebellum : a. Ganglion glo- 



ov T-rrvt*r r\f fVc fr\i*rmav> in bule, with its nucleus and nucleolus. 6. Nerve-tube, slight- 



m ly varicose, in close contact with the ganglion globule. &'. 



iTYiTnorlintp pnnnpvinn wifVi Smaller nerve-tubes. These parts all lie in a finely granular 



uauc ^uiiiiCAiUJO. vviLU. matrix interspersed with nuclei, c. B. Vesicular and fibrous 



4.} lpTn matter of the lamina* of the cerebellum, a. Ganglion glo- 

 bule. 6. Very minute nerve-tubes traversing a finely gra- 



Having premised this ge- nular matrix ' iu which are numerous loimded lluclei ' ' 

 neral account of the anato- 

 mical elements of the two 



kinds of nervous matter, we 

 may now consider separately 

 the two leading subdivi- 

 sions of the nervous system ; 

 namely, the nerves and the 

 centres. 



Of Nerves. A bundle of 

 nerve-fibres, surrounded and 

 connected by areolar tissue, 

 constitutes a nerve. 



The nerves of the cere- 

 bro-spinal system differ in 



several important particulars 



Fig. 58. 



,. From , the , Gasserian ganglion of an adult: a. a. Gan- 

 glion globules with their nucleus, nucleated capsule, and 



from tllOSe Of the SVmDatlie- pig 11 *- * Tubular fibres running among the globules 



\ * In contact with their capsule, g. Gelatinous fibres also in 



tlC, aild they Should, there- contilct with the ganglion globules. Magnified 320 dia- 



fore, be examined separately. 



Of the Cercbro -spinal Nerves. The areolar tissue which invests 

 the nerve-fibres is called the neurilemma. It is analogous to the 



