The holm oak, however, by its scarlet berry[2272] alone challenges competition with all these manifold productions. This grain appears at first sight to be a roughness on the surface of the tree, as it were, a small kind of the aquifolia[2273] variety of holm oak, known as the cusculium.[2274] To the poor in Spain it furnishes[2275] the means of paying one half of their tribute. We have already, when speaking[2276] of the purple of the murex, mentioned the best methods adopted for using it. It is produced also in Galatia, Africa, Pisidia, and Cilicia: the most inferior kind is that of Sardinia. CHAP. 13.—AGARIC. It is in the Gallic provinces more particularly that the glandiferous trees produce agaric;[2277] such being the name given to a white fungus which has a strong odour, and is very useful as an antidote. It grows upon the top of the tree, and gives out a brilliant light[2278] at night: this, indeed, is the sign by which its presence is known, and by the aid of this light it may be gathered during the night. The ægilops is the only one among the glandiferous trees that bears a kind of dry cloth,[2279] covered with a white mossy shag, and this, not only attached to the bark, but hanging down from the branches as well, a cubit even in length: this substance has a strong odour, as we have already[2280] stated, when speaking of the perfumes. The cork is but a very small tree, and its acorn is of the very worst[2281] quality, and rarely to be found as well: the bark[2282] is its only useful product, being remarkably thick, and if removed it will grow again. When straitened out, it has been known to form planks as much as ten feet square. This substance is employed more particularly attached as a buoy to the ropes[2283] of ships’ anchors and the drag-nets of fishermen. It is employed also for the bungs of casks and as a material for the winter shoes[2284] of females; for which reason the Greeks not inappropriately call them[2285] “the bark of a tree.” There are some writers who speak of it as the female of the holm oak; and in the countries where the holm does not grow, they substitute for it the wood of the cork-tree, more particularly in cartwrights’ work, in the vicinity of Elis and Lacedæmon for instance. The cork-tree does not grow throughout the whole of Italy, and in no[2286] part whatever of Gaul. CHAP. 14. (9.)—TREES OF WHICH THE BARK IS USED.