Reference for Chullin 256:30

ר' עקיבא אומר

And wherein is there a difference between R'Akiba and R'Jose the Galilean? - R'Papa answered: In the case of the kidney and the upper lip.<span class="x" onmousemove="('comment',' These are without bones, but obviously once cut away the animal cannot get another kidney or upper lip. According to R. Jose's definition these are regarded as limbs, but not so according to R. Akiba's definition.');">¹⁴</span>

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