ABSTRACT
From seminiferous tubules of the testis, snakes and other squamates possess a system of efferent ducts, at least some of which function not only in the passage of sperm but also in sperm storage and as accessory sex glands. The seminiferous tubules connect to the rete testis, which passes sperm sequentially to the ductuli efferentes, the ductus epididymis, and the ductus deferens. The sexual segment of the kidney, described in chapter 11, is a male accessory sex gland that passes secretions into the ureter. The ductus deferens merges with its ipsilateral ureter in viperid snakes, whereas the ductus deferens empties posterior to its ipsilateral ureter and into its ipsilateral ampulla urogenital papilla in colubroid snakes. The above description represents a new interpretation of the alignment and termination of the urogenital ducts in viperid and colubroid snakes and will be illustrated and discussed in detail later in this chapter. Eventually, all products within the adjoined urogenital ducts exit via a single urogenital papilla or paired urogenital papillae into the cloaca. Depending on taxon, species may have ampullae ductus deferentia, ampullae ureters, and/or ampullae urogenital papillae. In this chapter, we review the literature on these structures, provide much new information, and indicate directions for future research.
