We must take care, also, not to omit a peculiar shrub that is planted at Babylon, and only upon a thorny plant there, as it will not live anywhere else, just in the same manner as the mistletoe will live nowhere but upon trees. This shrub, however, will only grow upon a kind of thorn, which is known as the royal thorn.[1] It is a wonderful fact, but it germinates the very same day that it has been planted. This is done at the rising of the Dog-star, after which it speedily takes possession of the whole tree. They use it in the preparation of wine, and it is for this purpose that it is planted. This thorn grows at Athens also, upon the Long Walls there.[2]