Reference for Bava Batra 284:2

למימרא דהוא מיית ברישא והא הוה עובדא ופרכס תלתא פרכוסי אמר מר בר רב אשי מידי דהוה אזנב הלטאה שמפרכסת

dies first, surely there was a case when it made three convulsive movements?<span class="x" onmousemove="('comment',' After the mother was dead. ');">⁴</span> — Mar. son of R. Ashi, replied: Those were only [reflex movements] like those of the tail of the lizard which moves convulsively [even after it has been cut of].<span class="x" onmousemove="('comment',' Such movements are no signs of life. ');">⁵</span> Mar, the son of R. Joseph, said in the name of Raba: This<span class="x" onmousemove="('comment',' The Mishnah of Niddah cited, wherein a child one day old is mentioned, implying the exclusion of an embryo. ');">⁶</span>

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