Abstract
1) It is demonstrated on a new “glycerine spot method” (1952, Kotsuka) that there exist vagal vasoconstrictor fibers in the mesenterium of frogs and bullfrogs besides alrady verified vagal vasodilator fibers.
2) The above findings demonstrate that the blood vessels of frog's and bullfrog's mesenterium are subject to a double vagal innervation.
3) It is evidenced that there exist vagal vasoconstrictor fibers, vagal vasodilator fibers, anterior sympathetic vasoconstrictor fibers and posterior sympathetic vasodilator fibers in the vagosympathicus of frogs and bullfrogs. The blood vessels of mesenterium are subject to vasomotor innervation of these fibers.
