Can a single genus encompass two distinct genera?

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A single genus can contain two distinct categories, which become separate genera upon separation. For example, dates (as a genus) contain the pit (nawa) and the flesh, which are two distinct genera. Similarly, milk (laban) contains clotted cream (makhid) and butterfat (zabad), which are also two distinct genera. As long as these components maintain their natural physical connection (ittisal al-khilqa), they are treated as part of the single initial genus.