ELEMENTARY PHYSIOLOGY 



centre, be itself influenced by impulses which reach it 

 either from the brain above or the spinal cord below. In 



c.b Vg 



FlO. 23. — DiAORAM TO II.I-rsTRATE THR POSITION OF THE CaRPIO- 



Inhibitory Centre, the Paths of Inhibitory and Accelerator 



IlUTLSES FROM THE CENTRAL NERVOUS SVSTEM TO THE HeART, AND 



THE Course OF Impulses TO THE Centre from the Brain and from 



AN OUTLYING PaRT OF THE BoDY. 



Sp.C, Sp.C. spinal cord; C.f.C. cardio-inhibitory centre; X. vagus 

 nerve at its origin ; J'.G. ganglion of the vagus, through which run the 

 fibres coming from the centre along A7, the spinal accessory nerve (see 

 Lesson Xl.>. ('(/. main trunk of the vagus ; c.b. Vg. cardiac brifnches of 

 vagus, supplying the heart; C.Hii. sympathetic nerve in the neck; 

 S.C.O. superior cervical ganglion ; I.C.G. inferior cervical ganglion ; S.Art. 

 subclavian artery; A.V. annulus of Vieussens ; St.G. stellate ganglion ; 

 4, 0, (5, fourth, fifth and sixth thoracic ganglia ; c.b.Sji. cardiac branches 

 of the sympathetic su]>plying the heart. The dotted lines a./., a.f. 

 indicate paths of condiiction fur impulses to the cardio-inhibitory centre 

 from the bi-ain. The dotted lines »»../., m.f. indicate paths for the passage 

 of impulses to the cardio-inhibitory centre from some outlying part of 

 the body such as the stomach or intestines. The arrows show the 

 directions in which the impulses travel along each path. 



