3d. 5. The External Organs

(Partes Genitales Externæ Muliebres)

The external genital organs (Fig. 1171) of the female are: the mons pubis, the labia majora et minora pudendi, the clitoris, the vestibule of the vagina, the bulb of the vestibule, and the greater vestibular glands. The term pudendum or vulva, as generally applied, includes all these parts. 1 The Mons Pubis (commissura labiorum anterior; mons Veneris), the rounded eminence in front of the pubic symphysis, is formed by a collection of fatty tissue beneath the integument. It becomes covered with hair at the time of puberty. 2 The Labia Majora (labia majora pudendi) are two prominent longitudinal cutaneous folds which extend downward and backward from the mons pubis and form the lateral boundaries of a fissure or cleft, the pudendal cleft or rima, into which the vagina and urethra open. Each labium has two surfaces, an outer, pigmented and covered with strong, crisp hairs; and an inner, smooth and beset with large sebaceous follicles. Between the two there is a considerable quantity of areolar tissue, fat, and a tissue resembling the dartos tunic of the scrotum, besides vessels, nerves, and glands. The labia are thicker in front, where they form by their meeting the anterior labial commissure. Posteriorly they are not really joined, but appear to become lost in the neighboring integument, ending close to, and nearly parallel with, each other. Together with the connecting skin between them, they form the posterior labial commissure or posterior boundary of the pudendum. The interval between the posterior commissure and the anus, from 2.5 to 3 cm. in length, constitutes the perineum. The labia majora correspond to the scrotum in the male. 3

FIG. 1171– External genital organs of female. The labia minora have been drawn apart. (See enlarged image) The Labia Minora (labia minora pudendi; nymphæ) are two small cutaneous folds, situated between the labia majora, and extending from the clitoris obliquely downward, lateralward, and backward for about 4 cm. on either side of the orifice of the vagina, between which and the labia majora they end; in the virgin the posterior ends of the labia minora are usually joined across the middle line by a fold of skin, named the frenulum of the labia or fourchette. Anteriorly, each labium minus divides into two portions: the upper division passes above the clitoris to meet its fellow of the opposite side, forming a fold which overhangs the glans clitoridis, and is named the preputium clitoridis; the lower division passes beneath the clitoris and becomes united to its under surface, forming, with its fellow of the opposite side, the frenulum of the clitoris. On the opposed surfaces of the labia minora are numerous sebaceous follicles. 4 The Clitoris is an erectile structure, homologous with the penis. It is situated beneath the anterior labial commissure, partially hidden between the anterior ends of the labia minora. It consists of two corpora cavernosa, composed of erectile tissue enclosed in a dense layer of fibrous membrane, united together along their medial surfaces by an incomplete fibrous pectiniform septum; each corpus is connected to the rami of the pubis and ischium by a crus; the free extremity (glans clitoridis) is a small rounded tubercle, consisting of spongy erectile tissue, and highly sensitive. The clitoris is provided like the penis, with a suspensory ligament, and with two small muscles, the Ischiocavernosi, which are inserted into the crura of the clitoris. 5 The Vestibule (vestibulum vaginæ).—The cleft between the labia minora and behind the glans clitoridis is named the vestibule of the vagina: in it are seen the urethral and vaginal orifices and the openings of the ducts of the greater vestibular glands. 6 The external urethral orifice (orificium urethræ externum; urinary meatus) is placed about 2.5 cm. behind the glans clitoridis and immediately in front of that of the vagina; it usually assumes the form of a short, sagittal cleft with slightly raised margins. 7 The vaginal orifice is a median slit below and behind the opening of the urethra; its size varies inversely with that of the hymen. 8 The hymen is a thin fold of mucous membrane situated at the orifice of the vagina; the inner edges of the fold are normally in contact with each other, and the vaginal orifice appears as a cleft between them. The hymen varies much in shape. When stretched, its commonest form is that of a ring, generally broadest posteriorly; sometimes it is represented by a semilunar fold, with its concave margin turned toward the pubes. Occasionally it is cribriform, or its free margin forms a membranous fringe. It may be entirely absent, or may form a complete septum across the lower end of the vagina; the latter condition is known as an imperforate hymen. It may persist after copulation, so that its presence cannot be considered a sign of virginity. When the hymen has been ruptured, small rounded elevations known as the carunculæ hymenales are found as its remains. Between the hymen and the frenulum of the labia is a shallow depression, named the navicular fossa. 9 The Bulb of the Vestibule (bulbus vestibuli; vaginal bulb) is the homologue of the bulb and adjoining part of the corpus cavernosum urethræ of the male, and consists of two elongated masses of erectile tissue, placed one on either side of the vaginal orifice and united to each other in front by a narrow median band termed the pars intermedia. Each lateral mass measures a little over 2.5 cm. in length. Their posterior ends are expanded and are in contact with the greater vestibular glands; their anterior ends are tapered and joined to one another by the pars intermedia; their deep surfaces are in contact with the inferior fascia of the urogenital diaphragm; superficially they are covered by the Bulbocavernosus. 10

The Greater Vestibular Glands (glandulæ vestibularis major [Bartholini]; Bartholin’s glands) are the homologues of the bulbo-urethral glands in the male. They consist of two small, roundish bodies of a reddish-yellow color, situated one on either side of the vaginal orifice in contact with the posterior end of each lateral mass of the bulb of the vestibule. Each gland opens by means of a duct, about 2 cm. long, immediately lateral to the hymen, in the groove between it and the labium minus. 11

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