He has made a careful study of twenty-two cases of this malady. Most of his material is taken from the hospital at Merxhausen, which receives incurable insane females from the province of Hessen and the principality of Waldeck. Out of 700 patients, there were 185 idiots, 22 of whom, i. e., about 12 per cent., were affected with cerebral paralysis. He deals with all the symptoms and pathology of the affection. In such cases the paralysis and idiocy is complicated by a variety of nervous symptoms, especially with epilepsy, which affects at least half the patients, and helps to increase the mental deficiency. Dr. Wachsmuth's paper fills forty-four pages. His experience leads him to confirm the observation of Bourneville, that epilepsy generally disappears between the fortieth and fiftieth years of life. A great part of our cases, he observes, have already passed this age, and they have no more epileptic attacks. In other instances a diminution of the epileptic attacks has been observed. Many of the cases of cerebral paralysis are regarded as being the sequel of encephalitis, sometimes caused by infectious diseases. Wachsmuth does not consider the amount of paralysis is a measure of the mental deficiency. This study of the subject has induced him to divide his cases into four classes.