Reference for Chullin 252:29

רבי יהודה אומר

WITH REGARD TO A MOUSE WHICH IS HALF FLESH AND HALF EARTH.<span class="x" onmousemove="('comment',' According to the Rabbis, there exists a kind of mouse which is generated from the earth itself; v. Lewysohn, Zoologie des Talmuds, p. 345. Cf. also Sanh. 91a. In the process of generation there would be a time when it is half flesh and half earth.');">¹⁶</span>

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