If the white mulberry did not originally exist in Persia and in the neighbourhood of the Caspian Sea, it must have penetrated there a long while ago. I may quote in proof of this the name _tut_, _tutti_, _tuta_, which is Persian, Arabic, Turkish, and Tartar. There is a Sanskrit name, _tula_,[739] which must be connected with the same root as the Persian name; but no Hebrew name is known, which is a confirmation of the theory of a successive extension towards the west of Asia. I refer those of my readers who may desire more detailed information about the introduction of the mulberry and of silkworms to the able works of Targioni and Ritter, to which I have already referred. Recent discoveries made by various botanists have permitted me to add more precise data than those of Ritter on the question of origin, and if there are some apparent contradictions in our opinions on other points, it is because the famous geographer has considered a number of varieties as so many different species, whereas botanists, after a careful examination, have classed them together. +Black Mulberry+—_Morus nigra_, Linnæus. This tree is more valued for its fruit than for its leaves, and on that account I should have included it in the list of fruit trees; but its history can hardly be separated from that of the white mulberry. Moreover, its leaves are employed in many countries for the feeding of silkworms, although the silk produced is of inferior quality. The black mulberry is distinguished from the white by several characters independently of the black colour of the fruit, which occurs also in a few varieties of the _M. alba_.[740] It has not a great number of varieties like the latter, which argues a less ancient and a less general cultivation and a narrower primitive area. Greek and Latin authors, even the poets, have mentioned _Morus nigra_, which they compare to _Ficus sycomorus_, and which they even confounded originally with this Egyptian tree. Commentators for the last two centuries have quoted a number of passages which leave no doubt on this head, but which are devoid of interest in themselves.[741] They furnish no proof touching the origin of the species, which is presumably Persian, unless we are to take seriously the fable of Pyramus and Thisbe, of which the scene was in Babylonia, according to Ovid.