S. speaks with clenched teeth. His masseters are generally in a state of contraction, yet when he is requested to put out his tongue or to open his mouth, and when he is eating or engaged in an animated conversation, any and every movement of the inferior maxilla is accomplished with the greatest ease. According to his story, this tonic tic of the masseters had its origin in the forcible efforts he used to make to master his torticollis, in the course of which he would close his mouth firmly; by dint of continual repetition the habit developed into a tic, and persists apart altogether from any endeavour of his to prevail against the wryneck. One of us has had a recent opportunity of examining a young woman whose obsessions and fixed ideas, and tics of face and neck, indicated an extreme degree of mental instability, in spite of intellectual power above the average, in whom trismus of this type was very obvious during eating and speaking. No effort, however concentrated, to open the mouth was then of any avail; yet, on the other hand, she could sing to perfection, and she could yawn, or show her tongue or her throat, in an entirely easy and normal fashion. The appearance of this trismus during the performance of certain functional acts, and of these alone, is unequivocal evidence of its mental derivation. TICS OF THE NECK--NODDING AND TOSSING TICS--TICS OF AFFIRMATION, NEGATION, AND SALUTATION Regionally considered, the neck is second only to the face in furnishing the greatest number of tics. Convulsive movements of the neck muscles produce displacement of the head in all sorts of ways and directions, giving rise to clonic tics of affirmation, negation, and salutation, and to nodding tics, as well as to an important group of tonic tics which find expression in differing forms of torticollis. The latter are so distinctive in symptomatology and evolution, and have been the centre round which so much discussion has raged, that a chapter must be set apart for their special study. Restricting ourselves for the present to such as are included in the category of clonic convulsions, we find here abrupt vertical or horizontal movements, as well as intermediate varieties compounded of elevation, depression, inclination, or rotation. The most ordinary kind is a sudden, brief jerk or toss of the head, repeated at irregular intervals, and followed by instantaneous resumption of the primary position.