In a group of 7 operated dogs, atrophy of the laryngeal musculature begins 3-4 weeks after recurrent nerve division. The atrophy increases progressively as time runs out, so that at the ninth week (last control done) the degree of atrophy of the posterior cricoarytenoid muscle is well marked as compared with that of the initial stage (4-5 weeks). In another set of 8 dogs reinnervation of this muscle was successful in 5 animals. In some of them up to 36 months elapsed after the cutting of the recurrent nerve and 14 weeks after application of a neuromuscular graft (composed of the hypoglossal ansa and a sheet of sternothyroid muscle). Histologic recuperation was good in all cases, but in only 2 of them the motility of the vocal cord at stimulation of the branch of the nerve was effective. The conclusion drawn is that histologic regeneration does now always parallel the functional one. Nevertheless, it seems possible that the elapsing of more time should be necessary in order to restore motility. This point demands new and broader experience before a positive answer can be given.