Reference for Chullin 238:14

ת"ש דתנא דבי רבי ישמעאל

Granted, however, that the upper rows need the lower ones; but do the lower need the upper ones?<span class="x" onmousemove="('comment',' The lower rows of grain support the upper rows and if the lower rows were to fall away the upper rows, losing their support, would fall away too; hence from the point of view of the upper rows the entire ear of corn serves as one whole protection. On the other hand, the lower rows can stand without the upper ones for it has its own protection, and the fact that the upper and lower rows in the ear can be reckoned together proves that two protections can be reckoned together.');">⁹</span>

Jastrow

Jastrow

Jastrow

Jastrow

Jastrow

Jastrow