With the increasing publication of monographs on various branches of medicine, the compilation of a treatise on nervous and mental diseases, or on any other class of diseases, must become more and more tedious and difficult, readers becoming more and more critical. But, without being too exacting, one may still be disappointed with Dr. Carter Gray's work, and after careful perusal we can but award it lukewarm praise. As we shall have occasion to show, it is of decidedly unequal merit—some of the chapters, with the author, we take it, at his best, leave nothing to be desired; but in others we find but scant descriptions, and there are important omissions—omissions which we cannot (after reading the author's preface) qualify as non-essential.