The skin of primates. XXXI. The skin of the black‐collared tamarin (Tamarinus nigricollis)

The black‐collared tamarin represents the first detailed study of a member of the family Callithricidae. Although certain features are unique, some of its characteristics resemble those of Prosimii and those of Anthropoidea. The epidermis is moderately pigmented, and the dermis contains numerous elestic fibers. Scattered melanocytes are found throughout both layers. Hair follicles grow in groups of 3 to 4 over the general body surface, including the muzzle. One apocrine gland is associated with each hair group. In the periinguinal region is a large concentration of gigantic sebaceous glands. Apocrine glands occur over the entire hairy skin. Aggregations of these glands on the ventral wrist (in conjunction with sinus hairs) and chest represent the ulnar gland and suprasternal gland, respectively. Apocrine secretory coils of the ulnar gland and external genitalia are surrounded by melanotic, dendritic melanocytes. Eccrine sweat glands are confined to the volar surfaces of the pes and manus. Cholinesterase‐reactive granules are dispersed throughout the cytoplasm of the myoepithelial cells.