Henry Gray (18251861). Anatomy of the Human Body. 1918.
Enlarged view from the front of the left Wolffian body before the establishment of the distinction of sex. (From Farre, after Kobelt.) a, a, b, c, d. Tubular structure of the Wolffian body. e. Wolffian duct. f. Its upper extremity. g. Its termination in x, the urogenital sinus. h. The duct of Müller. i. Its upper, funnel-shaped extremity. k. Its lower end, terminating in the urogenital sinus. l. The genital gland.