Reference for Niddah 48:1

ושמואל מתרץ לטעמיה

Samuel also 'explains it in accordance with his view', thus: A four monthly embryo among small cattle, and an eight monthly one among large cattle, and one that is younger is equally forbidden. This, however, applies only to one whose period of pregnancy<span class="x" onmousemove="('comment',' Lit.,'its months'. ');">¹</span>

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