Fig. [19].—Annular Hymen.
In the new-born female infant, the hymen has the appearance of a tubular stopper closing the lower end of the vagina; according to Dohrn it exhibits as a rule one of three typical forms: Hymen annularis, denticulatus, et linguiformis; the annular, the denticulate, and the linguiform (or linguliform) hymen. The transverse ridges on the inner surface of the hymen, prolongations of the rugose columns of the vagina, are strongly developed. During the girl’s further growth, in association with the enlargement of the vagina, the hymen undergoes important changes in form and structure. Its border becomes thinner and more tense; and in the virgin at the time of the menarche, the annular hymen is the fundamental type, subject, however, to extensive variations. In most cases, at any rate, the aperture in the hymen is more or less centrally situated; very commonly, however, this opening is crescentic, when we have a semilunar hymen, the height of the border posteriorly being much greater than anteriorly. The consistency of the hymen, its extensibility, and its thickness, are as variable as its shape.
Fig. [20].—Semilunar Hymen.
Fig. [21].—Annular Hymen with congenital Symmetrical Indentations.
Fig. [22].—Fimbriate Hymen.
Fig. [23].—Deflorated Fimbriate Hymen.