2G8 riivsioi.oiiY OF Mrscu.s AND NF.IIVI s. 



(3) Tln-fi fin receivt an '.''il'mcnt transmitted to 

 ini'1 truiixiitiiti' if info conscious sensation. 



(4) Tin 1 ;/ are "/'/< t<> muse the mi^in-i-^lon (retar- 



,1 ill, m ) nj ,i a I.I-'IKI'I IKJ <:r<-!/< I,H nt. 



4. From t he above it must not be supposed that all 

 gangli< ni-cflls ])nssess all these qualities. On the con- 

 trary, it is to he supposed that each nerve-coll per- 

 forms but one of these functions, and even that there 

 arc more minute differences in them, so that, for in- 

 stance, the nerve-cells which accomplish sensation are 

 of various kinds, each of which accomplishes but one 

 distinct kind of sensation. This is no mere hypo- 

 thesis, for there are established facts which confirm 

 the view. Conscious sensations occur only in the brain, 

 and the various parts of the hraiii may be separately 

 remo\e. 1 or disabled, in which case individual forms 

 of sensation fail, while others remain undisturbed. 

 If the whole lirain is removed, the nerve-cells of the 

 dorsal marrow suffice fully to act ..... iplish the pheno- 

 mena of the transference of excitement I'mm one nerve- 

 fibre to another. Attain, there an- certain regions of 

 the brain which separately are able to give rise to inde- 

 pendent excifenienf. in themselves ; and certain accumu- 

 lations of nerve-cells which lie outside the actual central 

 nervous organs have the same power. The forms which 

 nerve-cells assume being very varied, it often happens 

 that the cells of certain regions, where only certain capa- 

 bilities can be shown, are alike in form, and differ in this 

 respect from the cells of other regions, where the capa- 

 bilities are different. As vvt. however, it has not been 

 found possible to distinguish differences in form sufti- 

 dentlycharacterisl Lc, and relations bel ween the form and 

 the function of nerve-cells sufficiently characf eri-t ic to 



