[Studies on the pudendal nerve. Part 4. A macroscopical observation of the branches of the pudendal plexus in dogs and cats (author's transl)].

The pudendal plexus and its branches of 20 dogs and 20 cats have been observed macroscopicaly. The main findings are summarized as follows: 1) The pudendal plexus in dogs is formed most frequently by the ventral rami of the first, second and third sacral nerves. 2) The bigeminal nerve of dogs and cats is formed respectively by the union of the ventral rami mentioned above. 3) The perineal nerve in dogs arises with one root from the bigeminal nerve and that of cats two roots, of which the main root arises from the points where the bigeminal nerve joins the asciatic nerve and the accessory one from the bigeminal nerve. 4) In dogs and cats the dorsal nerve of the penis or clitoris arises from the main trunk of the perineal nerve (Fig. 5, type IB) at an average rate of 57.5%. 5) In the dogs and cats, the inferior rectal nerve consists of two divisions; a division had the branches which are derived the perineal nerve to supply the skin around the anus and the other branches which arises from the muscular branch of the dorsal nerve of the penis or clitoris to supply the Sphincter ani externus. 6) The muscular branch of dogs and cats which is analogous to that of the perineal nerve in man, arises from the dorsal nerve of the penis or clitoris. 7) In dogs and cats the muscular branch to the Obturator internus is derived from the dorsal nerve of penis or clitoris. 8) The pelvic splanchnic nerve of dogs originates from the ventral rami of the first, second and third sacral nerves and that of cats from the ventral rami of the first and second sacral nerves. 9) In the posterior femoral cutaneous nerve in dogs, as well as in rats and rabbits, the lateral deviation of the origin from the sciatic to the perineal nerve is observed.