THE VISCERAL EFFERENT DIVISION. 1 99 



CHAPTER XII. 

 THE VISCERAL EFFERENT DIVISION. 



The visceral efferent division controls the smooth muscles 

 in the viscera and elsewhere in the body, the muscles of the heart 

 and blood vessels, certain striated muscles derived from the 

 lateral mesoderm, and the glands of the body. In higher verte- 

 brates at least, the smooth muscle and glands do not receive impulses 

 directly from the central nervous system, but the sympathetic 

 system offers intermediate neurones by which cerebro- spinal 



R. dors 



y Sym, 



FIG. 106. A diagrammatic representation of the visceral efferent components in 

 a trunk segment. 



impulses are carried (see following chapter). In the lower verte- 

 brates where the sympathetic system is poorly developed, it is 

 probable that some of the functions performed by it in higher 

 forms are performed by the visceral efferent nerves and centers. 

 As it is not possible at present to distinguish the excito-glandular 

 from the excito-motor cells in the central nervous system, the 



