L. is afflicted with abrupt blinking of the eyelids, retraction of the head, and elevation of the lip. Once the tic is established, it persists on an average for from eight days to a month, and during this time no effort on his part will check it. Sometimes he makes peculiar growling noises; sometimes he cannot prevent himself from stooping down as if to pick up stones; sometimes he is unable to restrain himself from touching everything within reach. From the age of five, C. exhibited frequent blinking movements, and gestures which seemed to indicate that his clothes were uncomfortable. No attempt at modification was attended with success. The tics steadily increased, till he found himself uttering cries and letting obscene words escape his lips. For a long time they remained in abeyance, then reappeared in his face and trunk, in the form of salutation movements. His propensity for clastomania, pyromania, and kleptomania necessitates his being kept under strict supervision, and though he is intelligent and has a good memory, he is also lazy and inattentive. Other tics of still greater complexity and peculiarity are met with among those whose psychical imperfections are very pronounced. Some "co-ordinated tics" are remarkable for their intricacy; they consist of a series of movements which mimic some act of everyday life. In this group may be specified various rhythmical movements, such as those of balancing, head rotation, and striking or beating oneself--the krouomania of Roubinowitch; they may be compared to the mother's rocking of her infant, inasmuch as they have a soothing effect on their subject, however brutal the movement itself sometimes may be. In most cases the patient is seated and rocks himself to and fro in an antero-posterior direction. Or it may be the head only that is rhythmically moved from side to side, and the performance may go on indefinitely. A mere touch or a word, on the other hand, is commonly sufficient to interrupt its sequence. There remains a final class of co-ordinated tics, which Noir distinguishes by the epithet "large," tics which are confined to idiots of good physical development. They consist of a movement or series of movements of considerable amplitude, and constitute the predominant clinical feature of the patient's idiocy. Here we find subjects who jump, or climb, or turn round and round; in other cases they are reduced to the level of mere automata, and go through a long series of actions in a mechanical way. Their memory for recent occurrences is very poor, but in their minds are stowed away vague souvenirs of events long past, which they translate into action, and which they are incapable of modifying, even as they are unable to add to their mental store or to alter their mental routine.