Fig. 427. Male Genital Organs of Cantharis vesicatoria.
a a. Testicle. b b. Vasa deferentia. cc, cc, cc, cc. The four pair of vesiculae seminales, or epididymoid vessels. d. The common spermatic tube. e. Portion of the intestinal tube inverted. f. Last abdominal ring.
This image is from _ in Pereira's Elements of Materia Medica and Therapeutics, 1854.