In the case of a fibroid tumor situated in the central stratum of fibres the antagonism is equal at all points, and it is evident that there is no tendency to rupture of the capsule, and much less crushing influence exerted upon it than if it were situated slightly nearer the mucous membrane. This variety of the tumor, therefore, yields to ergot only as it may be starved out by diminution of its blood-supply and as the effect of pressure, which we all know are the two conditions most favorable to absorption. Now I think we have arrived at a point in this investigation where we can draw inferences as to the forms of tumors likely to be effected by ergot in different ways, as well as those that will not be effected by it. We do not expect ergot to cause painful and efficient contractions in the healthy unimpregnated uterus; its fibres are not capable of such contraction, and it is not until the fibres have become greatly developed that they are susceptible to the impressions of ergot. In cases of early abortion its action is very unreliable, but after the fourth month of pregnancy it acts quite efficiently. In tumors of the uterus the development of the fibrous structure is sometimes so slight that it is incapable of contraction; there may be so many nuclei of degeneration that there are not enough sound fibres left for efficient contraction. Then, where there are many small tumors developed in the uterine walls, the circulation is cut off to such a degree that they degenerate into a cartilaginoid substance, and sometimes they are infiltrated with calcareous material. In none of these cases will ergot cause any appreciable results. When, however, there are {265} but one, two, or three nuclei of morbid growths, as they increase in size the fibres undergo the development necessary to enable them to contract with great efficiency and render them susceptible to the influence of ergot. Another condition which influences the hypertrophic growth of the fibres is the situation of the tumor. Subperitoneal tumors do not cause as great growth in the fibres of their neighborhood as the intramural or submucous varieties. A single intramural tumor causes great development of the whole uterine tissues, but the development of the wall in which it is situated decidedly predominates. The submucous neoplasm so soon gains the uterine cavity that the development is nearly the same in the whole organ. When, therefore, we administer ergot for the cure of fibrous tumors of the uterus, the beneficial action of the drug will depend upon the degree of development of the fibres of the uterus and the position of the tumor with reference to the serous or mucous surface. The nearer the mucous surface, the better the effects. If the tumor is very near the lining membrane, we may hope for its expulsion en masse or by disintegration.