Macfadyen,[898] on the contrary, in his _Flora of Jamaica_, says, “It is a well-established fact, familiar to every one who has been any length of time in this island, that the seed of the sweet orange very frequently grows up into a tree bearing the bitter fruit, numerous well-attested instances of which have come to my own knowledge. I am not aware, however, that the seed of the bitter orange has ever grown up into the sweet-fruited variety.... We may therefore conclude,” the author judiciously goes on to say, “that the bitter orange was the original stock.” He asserts that in calcareous soil the sweet orange may be raised from seed, but that in other soils it produces fruits more or less sour or bitter. Duchassaing says that in Guadeloupe the seeds of sweet oranges often yield bitter fruit,[899] while, according to Dr. Ernst, at Caracas they sometimes yield sour but not bitter fruit.[900] Brandis relates that at Khasia, in India, as far as he can verify the fact, the extensive plantations of sweet oranges are from seed. These differences show the variable degree of heredity, and confirm the opinion that these two kinds of orange should be considered as two varieties, not two species. I am, however, obliged to take them in succession, to explain their origin and the extent of their cultivation at different epochs. +Bitter Orange+—_Arancio forte_ in Italian, _bigaradier_ in French, _pomeranze_ in German. _Citrus vulgaris_, Risso; _C. aurantium_ (var. _bigaradia_), Brandis and Hooker.