成唯識論演祕 3.89

3.89

乘前為問。第八不熏，無果俱義；第七既熏，六義具矣，故應名種。

This follows upon the preceding to pose a question. The eighth [consciousness] does not perfume, so it lacks the meaning of being simultaneous with the fruit; but since the seventh perfumes, it possesses all six meanings, and hence it should be called a bīja.