A text-book of physiology, for medical students and physicians . of vagus inhibitionit seems often to show a notice-able improvement in condition. That the inhibitory ef-fect of the vagus im-pulses upon the heart isnot due to any peculiarityin properties of thesefibers or of the impulsesthemselves, but is depend-ent rather upon the placeor manner of ending in theheart, has been demon-strated by direct experi-ment. Erlanger* has shownthat when an ordinaryspinal nerve (fifth cervical)is sutured to the peripheralend of the cut vagus, it will,after time for regenerationhas been allowed, cause,when
A text-book of physiology, for medical students and physicians . of vagus inhibitionit seems often to show a notice-able improvement in condition. That the inhibitory ef-fect of the vagus im-pulses upon the heart isnot due to any peculiarityin properties of thesefibers or of the impulsesthemselves, but is depend-ent rather upon the placeor manner of ending in theheart, has been demon-strated by direct experi-ment. Erlanger* has shownthat when an ordinaryspinal nerve (fifth cervical)is sutured to the peripheralend of the cut vagus, it will,after time for regenerationhas been allowed, cause,when stimulated, the usualstoppage of the heart. The Course of the Ac-celerator Fibers.—Theheart receives efferent ormotor nerve fibers fromthe sympathetic system in addition to those reaching it by way of the vagus nerve. Atten-tion was first called to these sympathetic fibers by Legallois(1812), but our recent knowledge dates from the experimentsmade by von Bezold (1862), which were afterward completed* Erlanger, American Journal of Physiology, 13, 372, Fig. 235.—Schematic representation of thecourse of the accelerator fibers to the dogs heart—right side.—(Modified from Pawlow.) The sym-pathetic nerve is represented in solid black. Thecourse of the accelerator fibers is indicated by ar-rows. /, Cervical sympathetic combined in heckwith, 10, the vagus; //, ///, IV, rami communi-cantes from the second, third, and fourth thoracicspinal nerves, carrying most of the accelerator fi-bers to the sympathetic chain; 7, annulus of Vieus-sens; 8, inferior cervical ganglion; 2, 3, 4, 5,branches from vagus and vago-sympathetic trunkgoing to cardiac plexus (some of these—3, 5,—carry accelerator fibers; 9, the inferior laryngealnerve. 572 CIRCULATION OF BLOOD AND LYMPH. by the Cyon brothers—M. and E. Cyon*—1866. These fiberswhen stimulated cause an increased rate of beat and are, there-fore, designated as the accelerator nerve of the heart. Theircourse has been worked out
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