In fowl, the term "phallus" refers to a rudimentary, non-intromittent structure located on the ventral lip of the vent (cloaca) in males. Unlike mammals, birds generally don't have a penis for intromission. In chickens and turkeys, this phallus is a small, rounded structure formed by two lateral phallic bodies separated by a median groove. This structure is involved in the passage of semen during reproduction, becoming engorged with lymph to facilitate this process.