Order XLII
ZYGOPHYLLEÆ.
The hardness of the wood of the shrubby species of this order is most remarkable, if the softness of the stems of the herbaceous ones is remembered. To this the extreme difficulty of propagating Guaiacum is to 3Y3 NATURAL ARRANGEMENT. be attributed. Zygophyllum Fabágo is employed as an anthelmintic, but it is in the Guaíacum that the great medical virtues of the order are found: all the genus is extremely exciting; the wood and bark of Guaíacum officinále and sánctum have a rather bitter acrid flavor, and are principally used as sudorifics, diaphoretics, or alteratives; they have been found to contain a particular substance differing both from gum and resin, which has been called guayacine. Many of the species bear beautiful flowers, especially the Tribuluses, which with their brilliant yellow Cistus-like blossoms, enliven many a barren rock in the tropics. None are found in the colder latitudes of the world. 993 Guaíacum W. 994 Zygophyllum W. 995 Fagónia W. 996 Tríbulus W.