The inner lips, the nymphæ or labia minora, running parallel with the greater lips which enclose them, embrace the clitoris anteriorly and extend backward, enclosing the urethral exit between them as well as the vaginal entrance. They form little wings whence their old Latin name, _alæ_, and from their resemblance to the cock's comb were by Spigelius termed crista galli. The red and (especially in brunettes) dark appearance of the nymphæ suggests that they are mucous membrane and not integumentary; it is, however, now considered that even on the inner surface they are covered by skin and separated from the mucous membrane by a line.[90] In structure, as described by Waldeyer, they consist of fine connective tissue rich in elastic fibers as well as some muscular tissue, and full of large veins, so that they are capable of a considerable degree of turgescence resembling erection during sexual excitement, while Ballantyne finds that the nymphæ are supplied to a notable extent with nervous end-organs. More than any other part of the sexual apparatus in either sex, the lesser lips, on account of their shape, their position, and their structure, are capable of acquired modifications, more especially hypertrophy and elongation. By stretching, it is stated, a labium can be doubled in its dimensions. The "Hottentot apron," or elongated nymphæ, commonly found among some peoples in South Africa, has long been a familiar phenomenon. In such cases a length or transverse diameter of 3 to 5 centimeters is commonly found. But such elongated nymphæ are by no means confined to one part of the world or to one race; they are quite common among women of European race, and reach a size equal to most of the more reliably recorded Hottentot cases. Dickinson, who has very carefully studied this question in New York, finds that in 1000 consecutive gynæcological cases the labia showed some form of hypertrophy in 36 per cent., or more than 1 in 3; while among 150 of these cases who were neurasthenic, the proportion reached 56 per cent., even when minor or doubtful enlargements were disregarded. Bergh, in about 16 per cent. cases, found very enlarged nymphæ, the height reached in about 5 per cent. of the cases of enlargement being nearly six centimeters. Ploss and Bartels, in a full discussion: of the "Hottentot apron," come to the conclusion that this condition is perhaps in most cases artificially produced. It is known that among the Basutos it is the custom for the elder girls to manipulate the nymphæ of younger children, when alone with them, almost from birth, and on account of the elastic nature of these structures such manipulation quite adequately accounts for the elongation. It is not necessary to suppose that the custom is practiced for the sake of producing sexual stimulation--though this may frequently occur--since there are numerous similar primitive customs involving deformation of the sexual organs without the production of sexual excitement.