The symptoms of parovarian cysts resemble those of ovarian cysts of similar development. On account of the intra-ligamentous development of the tumor, pressure-symptoms may appear early. The cyst is of such slow growth that the simple parovarian cyst may exist for a long time without giving any trouble whatever. The slow growth is the only clinical feature that would enable one to make a diagnosis between parovarian and ovarian cyst. COMPARISON OF OÖPHORITIC, PAROÖPHORITIC, AND PAROVARIAN CYSTS. The chief characteristic features of the large cysts of the ovary and the parovarium--the glandular cyst, the paroöphoritic cyst, and the parovarian cyst--may be tabulated for comparison as follows: [Illustration: FIG. 171.--Section, perpendicular to the long axis of the Fallopian tube, passing through the tube, the parovarium, and the ovary; showing the relation of the structures to the peritoneum of the broad ligament.] [Illustration: FIG. 172.--Section, perpendicular to the long axis of the Fallopian tube, showing the relation of an oöphoritic cyst to the peritoneum of the broad ligament.] [Illustration: FIG. 173.--Section, perpendicular to the long axis of the Fallopian tube, showing the relation of a paroöphoritic cyst to the oöphoron and the peritoneum of the broad ligament.] =Glandular Oöphoritic Cyst.=--Intra-peritoneal in development; no peritoneal investment. Ovary destroyed early in the course of the disease. Cyst multilocular. Fluid contents thick, colored; specific gravity greater than 1010. Tumor of rapid growth. Usually unilateral. Fallopian tube distinct from tumor, and not much, if any, elongated. =Paroöphoritic Cyst.=--Often extra-peritoneal in development, in which case there is a detachable peritoneal investment. Oöphoron not at first involved by the growth. Unilocular. Fluid contents less thick and viscid than in oöphoritic cyst. Interior filled with papillomata. Tumor usually of slower growth than the oöphoritic cyst. Very often bilateral. Fallopian tube more likely to be involved than in oöphoritic cyst. [Illustration: FIG. 174.--Section, perpendicular to the long axis of the Fallopian tube, showing the relation of a parovarian cyst to the ovary, the tube, and the peritoneum of the broad ligament.] =Cysts of the Parovarium.=--Intra-ligamentous in development. Peritoneal investment which may be stripped off. Ovary pushed aside, but shape not affected unless the cyst be very large. Cyst unilocular. Wall thin. Fluid contents watery, opalescent; specific gravity below 1010. May or may not have papillomata in interior. Tumor of very slow growth. Usually unilateral. Fallopian tube much elongated and stretched immediately over the surface of the cyst. CHAPTER XXXI. NATURAL HISTORY AND TREATMENT OF OVARIAN CYSTS.