Further, it seemed to me desirable to keep periodic, separate from permanent squint; this, however, could not be accomplished with exactness. It may easily happen that children with periodic squint always squint just when one sees them, and in those cases which had already been operated on when they came to be examined, it was quite impossible to determine whether periodic or permanent squint had formerly been present. Therefore I have represented separately in each particular group the number of those previously operated on. In the following table the refraction of the fixing eye and the visual acuteness of the squinting eye are given. In alternating squint the refraction of the emmetropic eye was taken, as determining it for insertion in the lower division of the statistics. A. Convergent squint with myopia: 1. Slight myopia to M. = 1·75 D. (_a_) Permanent squint 11 cases (3 previously operated on). Anisometropia in 2 cases (one with M. 1·25 D. of the fixing, M. 4 D. of the squinting eye; the other with M. 1·25 D. of the fixing, H. 4 D. and V. = 1 of the squinting eye). The examination of the visual acuteness of the squinting eye showed: V. more than 1/7 4 cases. V. 1/12 - 1/18 1 case. V. 1/24 - 1/36 1 case. V. Less than 1/36 4 cases (among them one with H. 2 D. in the squinting eye.) V. indeterminable 1 case.