Recently, I reported1 that the spinal accessory nerves of the cat and the monkey are not purely motor, as is generally supposed. A few nerve cells of the sensory type were observed scattered along their course, and even small ganglia were found occasionally.2 Aberrant collections of neurons are known to occur in man3 also. That those observed in the cat are associated with fibers in the nerve seems to be indicated by the fact that they undergo chromatolysis when the eleventh nerve is cut at its place of entrance into the sternocleidomastoid muscle. These observations raised the question of the possible presence of similar neurons in the motor roots of the spinal nerves. It was realized that a search might not yield any, because the ventral spinal roots are not homologous to the accessory; nevertheless, a survey of the literature revealed that other observers have reported such