Yevamot 83a and Yevamot 83b, along the way to figuring out the status of an androgynos, discussion of four topics where Rav and Shemuel thought we followed R. Yose and R. Shim’on, two by Rav and two by Shemuel, and then back to whether an androgynos is treated fully as a man, or as possibly a man, and for what areas of halacha.