Bidder’s canal is present inside kidney of frog. It receives sperms from testes via a number of vasa efferentia. Vasa-efferentia open into the bidders canal and the bidders canal is connected to longitudinal collecting tubules by means of a number of transverse collecting ducts and helps in passing of the sperms. It communicates with the ureter, which leaves the kidney near its kind end and opens into the cloaca.
In frogs, testes and kidney are present very close to each other. The sperms are transferred from the testes into bidder’s canal through vasa efferentia. The Bidder’s canal remains connected to the ureter by transverse walls and forms the urogenital duct which opens into cloaca from where both sperms and urine are passed out.