I have as yet spoken as if the varieties of the same species were invariably fertile when intercrossed.

到目前为止， 我已经说过， 好像同一物种的变种在杂交时总是能生育。

The view commonly entertained by naturalists is that species, when intercrossed, have been specially endowed with sterility, in order to prevent their confusion.

博物学家普遍持有的观点是， 物种在杂交时被特别赋予了不育性， 以防止它们混淆。

Pure species have of course their organs of reproduction in a perfect condition, yet when intercrossed they produce either few or no offspring.

纯种当然有完美的繁殖器官，但当杂交时， 它们要么很少， 要么没有后代。

It cannot be maintained that species when intercrossed are invariably sterile and varieties invariably fertile; or that sterility is a special endowment and sign of creation.

不能认为杂交时的物种总是不育的， 而变种总是能育的； 或者不育是一种特殊的天赋和创造的标志。