Fig. 12. White Plants. not uncommon in southern Arizona, where Agave Palmeri was much eaten; and they are to be seen in the Grand Canyon, in northern Arizona, where A. Utahensis is abundant.

The most important economic agaves are not the source of alcohol, but those which yield 'henequen,'—a native name introduced by Oviedo only a few years after Yucatan was discovered. This, so far as Mexico is concerned, is practically a product of Yucatan, though some of the other tropical states Fig. 14. Sotol. yield a small quota, and it has a yearly value of some $30,000,000 gold. A large part of it comes to the United States for use in cordage, etc., under the name 'sisal hemp' or 'sisal grass,' which is derived from a port of shipment. Our imports for the past three years average about $15,000,000 annually.

Most of the agaves have a strong fiber in their leaves, the use of which is prehistoric. That of the century plant is particularly white and fine, and, as I have said, is considerably used. The fiber of the pulque species, from the manner in which the sap is gathered, is little used; the very fleshy-leaved species are also hard to clean. The Tequila mezcal Fig. 13. Half-naked Laborers. is said to produce a good quality of fiber, which—its harvesting not interfering with the main use of the plants—is coming to be regarded as a valuable by-product of this species; and several other agaves are either cultivated on a smaller scale for their fiber or exploited as they occur spontaneously.