Reference for Chullin 272:2

אי מה תרומה ממין על שאינו מינו לא

Again just as in the case of terumah one may not give one kind [as terumah] for another kind,<span class="x" onmousemove="('comment',' Even though both kinds are of the same species; cf. infra black figs and white figs.');">²</span>

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