It is the most important species yet known.

This you will readily admit when I tell you that from it comes all our silk--spun out of it by the silkworm (_Bombyx mori_).

It is called white mulberry on account of the colour of its fruit, which, however, is not always white, but sometimes of a purple or black colour.

Now it would be difficult to give an exact description of a white mulberry-tree; for, like the apple and pear trees, there are many varieties of it produced from the same seeds, and also by difference of soil and climate.

It is a small tree, however, rarely growing over forty feet high, with thick leaves and numerous branches.