88 



Journal of Comparative Neurology, 



most respects. We may, therefore recognize c&xt^.m functional 

 divisions of the whole nervous system, and note that the suc- 

 cessive parts of each division present a serial homology. A 

 given functional division consists of all the peripheral end-organs 

 belonging to a given type, the nerve components which connect them 

 with the brain, and the brain center in ivhich these componeiits end 

 or take their ongin. Several such functional divisions, sensory 

 and motor, constitute the reflex apparatus which governs the 

 body. There are added to this on the one hand the specialized 

 sympathetic system, and on the other hand the "higher brain 

 centers" which serve for more complex interrelation and coor- 

 dination, and in higher vertebrates for voluntary (conscious) 

 activities. The scope of the present paper does not admit the 



Fig. I . — Diagram of the functional divisions in the region of the medulla. 

 b. — end-buds ; g. c. — general cutaneous components ; g. v. — general splanchnic 

 components; /. h. — lateral horn or nucleus ambiguus ; /. v. — lobus vagi or fasci- 

 culus communis ; ni. s. — somatic musculature ; m. v. — visceral musculature ; 

 n. — neuromasts ; s. m. — somatic motor division ; sp. m. — splanchnic motor di- 

 vision ; sp. s. — Splanchnic sensory division; s. s. — somatic sensory division; 

 /. a. — tuberculum acusticum ; v. k. — ventral horn. 



discussion of the sympathetic system. It is proposed to com- 

 pare the chief features of the functional divisions in the trunk 

 and head regions, and to inquire briefly how far the brain itself 



