Histological Study on the Sensory Innervation of the Perivulval Skin of Female Formosan Macaque

Abstract

The female Formosan macaque has no labium majus pudendi. The part between the labium minus pudendi and the ischial callosity which we wish to call the perivulva is covered by a thick epidermis with a cornified plate and the papillae growing into it out of the corium are very well developed, recalling what has been observed in the palm of the hand and the sole of the foot.
This special skin part is considerably well provided with sensory nerve fibres to match such a histological feature. The numerous sensory fibres coming into this part end not only in unbranched and simple branched terminations but also in corpus cular terminations or complex branched terminations never found in the common haired skin. Intraepidermal branched terminations are not rare either. The corpuscular terminations here are of the Type I of end-bodies (YAMAMOTO) and show glomerular arrangement. The complex branched terminations originate in stem fibres thicker than those of the unbranched and the simple branched terminations; their numerous branch fibres often show change in size and end either sharply or bluntly just beneath the epidermis, but in some cases in the epidermis, and even far up near its cornified surface layer.