Insanity in any of its forms may be accompanied by clonic or tonic convulsive movements--movements that may be of the nature of tics or spasms or stereotyped acts, or that may belong to conditions which we distinguish by the names of myoclonus, polyclonus, myotonia, catatonia, etc. It is highly probable that many instances have been described as spasms which, according to our nomenclature, must be considered tics. Brodie, to take an example, quotes a case where a "spasm" of the spinal accessory was replaced by a mental affection. Alternation of hallucinatory mental confusion with "spasm" of the neck muscles has been observed by Oppenheim, as well as a case where the "spasm" originated in the course of an attack of alcoholic mania. In another, due to Gowers, "spasm" of the muscles of the neck was preceded, at a ten years' interval, by an attack of melancholia. Most of the cases of this nature would be held to-day to be instances of mental torticollis. That tics and mental disease accompany each other is notorious, but a discussion of the question would carry us beyond our limits. We must say a word, however, on the tics of idiots. The study of tic as it occurs in idiots, imbeciles, and _arriérés_, has engrossed the attention of alienists since the days of Pinel and Esquirol. Cruchet says the mental state of the idiot and the imbecile is so characteristic that the diagnosis of convulsive tic in such cases is never attended with any difficulty. Yet the task is sometimes sufficiently delicate, for we maintain that upon our insight into the subject's mental condition depends our ability to analyse his tics. Considerable light has been thrown on the question by the important information amassed by Bourneville, as well as by the fine psychological studies of Sollier and the meritorious thesis of Noir, from which we shall borrow largely in this place. In the first instance, we meet with tics in every way comparable to those we have already described, and we may give one or two examples. R. accidentally wounded his left eye at the age of eleven, and contracted a tic which consists in spasmodic blinking of the eyelids, though no sign of ocular lesion is left. A diminution in its intensity has been taking place, which has culminated recently in its spontaneous disappearance. N. had an attack of ciliary blepharitis and keratitis which left an opaque patch on the upper and inner part of his left cornea, and he has blinked ever since. Yet there is no local irritation to justify the continuance of the movements. The tics are occasionally as numerous and violent as in Gilles de la Tourette's disease, and are accompanied with cries and with coprolalia.