17. Reproductive Systems in Non-mammalians Arthropods -males develop sperm in testes, and are conveyed through a coiled duct to two seminal vesicles -females develop eggs in a pair of ovaries and are conveyed to vagina through ducts * spermatheca: sac that stores sperm for long periods of time in female reproductive system Cloaca: common opening of the digestive, excretory, and reproductive system