Licence: Public Domain Mark
Credit: The uterus and its appendages. Source: Wellcome Collection.
Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.
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![from their supposed office in suspending the ovum, and retaining it in its proper situation in the Graafian follicle. That the retinacula, however, are not essen- tial structures is proved by the fact that they are wanting in many of the Mammalia as well as in Man. They have been observed chiefly in the Rodentia and Ruminantia, where their form and number are subject to considerable varia- tion. The subjoined figure exhibits the ovum Fig. 376. Ooum of rabbit surrounded by the tunica granulosa and portions of retinacula. (After Coste.') surrounded by the layer of granules which constitutes the tunica granulosa, and externally to this the radiating bands or retinacula, the whole of those parts, external to the ovum, being composed of nucleated cells. Besides these structures, the Graafian follicle contains a pellucid albuminous fluid, of a slightly yellowish colour, partially coagulable by heat. In this fluid float numerous granules similar to those of which the parts just de- scribed are formed, together with a varying quantity of oil-like globules. Lastly, in the midst of the granules at an early period, and subsequently in that more de- finite arrangement of them which constitutes the tunica granulosa, is contained the ovum (fig. 374. f and Jig. 376.), a full description of which is given in the article under that title. 4. Vessels and Nerves.—The ovary de- rives its supply of blood chiefly from the ovarian (spermatic), but in part also from the uterine arteries. So free, indeed, is the com- munication between these vessels, that the organ may be equally well injected from either source. The communication is effected chiefly by means of a branch of the ovarian artery, which passes inwards to inosculate with a ter- minal branch of the uterine artery, this anas- tomotic branch being occasionally so large as to constitute the principal source of supply of the ovary. The terminal vessels are con- ducted to the lower border of the ovary be- tween the folds of the posterior duplicature of the broad ligament, where they lie in parallel lines, and are readily distinguished by their tortuous or spiral form. Having en- tered the base of the organ, they spread out into those numerous ramifications which pene- trate every part of the ovarian stroma, and give to this structure its peculiar fibrous as- pect. From their extreme branches the blood is returned by the veins, which pass to the base of the organ, where they are very numerous (fig. 370. h). They form, near the ovary and between the folds of the broad ligament, a plexus termed the ovarian or pampiniform plexus, (fig. 369. d) the vessels of which com- municate also with the uterine plexus. Valves are found in the ovarian veins only in exceptional cases. The ovary derives its nerves from the renal and inferior aortic plexuses.* The nerves enter the organ along with the blood-vessels. Functions of the Ovary. The ovary is to the female what the testis is to the male—the germ-preparing organ, the part in which is formed the female generative element, and therefore the essential portion of the entire sexual apparatus. To it all other structures may be regarded as accessory or superadded ; for in by far the largest proportion of the animal kingdom they are either found in a rudimentary state, or else have no existence. But not only is the ovary the organ in which the formation and evolution of the germ take place ; its offices farther extend to the separa- tion and expulsion of the ova, when they have reached such a state of maturity as will render them susceptible of impregnation. This process, commonly termed ovulation, takes place spontaneously, and without the intervention of the male, which is not neces- sary thereto. All animals possessing an ovary are subject to this law; and Man constitutes no exception to the rule. But the functions of the ovary are exercised only during a cer- tain period of life. The ova, which are formed at or near the time of birth, and sometimes before that event, are not called into activity until the body of the parent is sufficiently developed, to suffer the parturient act without destruction or serious detriment to its own tissues, such as would be incompatible with the continuance of its own life, and such as is witnessed in those lower tribes where the whole of the vital energies of the parent are exhausted by one effort of reproduction, or its tissues are even disrupted by the process which produces its kind. But long before the time arrives at which the generative faculty is capable of being fully exercised, it is probable that many of the ova which were first formed have perished, their place being continually supplied by new formations.-]' Their numbers, however, are so great that, if only the one thousandth part of those originally contained * Snow Beck, Phil. Trans. 1846, part ii. f Barry, Phjl. Trans. 1888, part ii. p. 319. Dr. Ritchie, Med. Gaz., vols. xxxiii., xxxiv.](https://iiif.wellcomecollection.org/image/b2499201x_0018.jp2/full/800%2C/0/default.jpg)
