uterus being irritated to contract by the effused blood between itself and the membranes. In patients who have suffered from attacks of dysmenorrhoea in the unimpregnated state, the irritable uterus, when pregnant, is very apt to contract upon its contents and expel them. This usually happens at what would have been a menstrual period, and not unfrequently takes place so soon after impregnation as merely to be looked upon as an unusually severe attack, the little ovum having been imperceptibly expelled among the discharges. Under this head must be brought those cases of spasmodic affection of the uterus, which Dr. Burns has described, and where, from the diminutive size of the ovum, the case has rather resembled one of menorrhagia. Cases of abortion are also mentioned by authors where the uterus is stated to be incapable of undergoing the necessary dilatation and increase of size which pregnancy requires; but we are strongly disposed to refer them to the above head of great uterine irritability, as we neither know of any diagnostic marks which will enable us to detect this condition during life, nor are we aware of any physical condition of the uterus short of actual disease, to be detected after death, which can produce this inability. The uterus may be also excited to expel the foetus, without its previous death by local causes, as acute leucorrhoea, or other inflammatory affections of the vagina, by inflammation and other affections of the bladder, as calculus, &c. Too frequent sexual intercourse during the early months of pregnancy is peculiarly liable to excite abortion: this is especially observed among primiparæ of the better ranks, where, from luxurious living, &c., there is but little physical strength in proportion to the great irritability of the system: hence we find that a fifth, or even a fourth, of these females abort in their first pregnancies. In conclusion we may briefly state that the same circumstances which in the unimpregnated condition produce menstrual derangement and other disorders of the uterine system, now act as so many causes of abortion.