Botanists have not yet furnished any certain proof that this species is indigenous in Persia. Boissier, who is the most learned in the floras of the East, contents himself with quoting Hohenacker as the discoverer of _M. nigra_ in the forests of Lenkoran, on the south coast of the Caspian Sea, and he adds, “probably wild in the north of Persia near the Caspian Sea.”[742] Ledebour, in his Russian flora, had previously indicated, on the authority of different travellers, the Crimea and the provinces south of the Caucasus;[743] but Steven denies the existence of the species in the Crimea except in a cultivated state.[744] Tchihatcheff and Koch found the black mulberry in high wild districts of Armenia. It is very probable that in the region to the south of the Caucasus and of the Caspian Sea _Morus nigra_ is wild and indigenous rather than naturalized. What leads me to this belief is (1) that it is not known, even in a cultivated state, in India, China, or Japan; (2) that it has no Sanskrit name; (3) that it was so early introduced into Greece, a country which had intercourse with Armenia at an early period.[745] _Morus nigra_ spread so little to the south of Persia, that no certain Hebrew name is known for it, nor even a Persian name distinct from that of _Morus alba_. It was widely cultivated in Italy until the superiority of the white mulberry for the rearing of silkworms was recognized. In Greece the black mulberry is still the most cultivated.[746] It has become naturalized here and there in these countries and in Spain.[747] +American Aloe+—_Agave Americana_, Linnæus. This ligneous plant, of the order of _Amaryllidaceæ_, has been cultivated from time immemorial in Mexico under the names _maguey_ or _metl_, in order to extract from it, at the moment when the flower stem is developed, the wine known as _pulque_. Humboldt has given a full description of this culture,[748] and he tells us elsewhere[749] that the species grows in the whole of South America as far as five thousand feet of altitude. It is mentioned[750] in Jamaica, Antigua, Dominica, and Cuba, but it must be observed that it multiplies easily by suckers, and that it is often planted far from dwellings to form fences or to extract from it the fibre known as _pite_, and this makes it difficult to ascertain its original habitat. Transported long since into the countries which border the Mediterranean, it occurs there with every appearance of an indigenous species, although there is no doubt as to its origin.[751] Probably, to judge from the various uses made of it in Mexico before the arrival of the Europeans, it came originally from thence. +Sugar-Cane+—_Saccharum officinarum_, Linnæus.