Hullin 70: The Surgical Activity of a Weasel

More on case of the fetus -- when does the principle of "majority" apply to limbs emerging? Or does it ever? When is it considered as if it was born? What if half of the fetus has emerged, but a majority of a particular limb? A nuanced, and likely boundary-pushing case. Also, what if the fetus were wrapped while it was still internal? Is that a barrier to the sanctity of the first-born? What about its amniotic sac? What about shenanigans by a weasel that removes and replaces the fetus? Also - a new mishnah about whether the fetus is pure or impure, as per the parent, or (as the main view in the mishnah stipulates), the fetus is inherently pure and won't convey impurity. The Gemara probes this rationale. Plus, an important distinction between animals' feet - when they are paws as compared to cloven hooves.