144 FAMILIES OF FLOWERING PLANTS 
Family Erythroxylaceae. Redwood family. Contains two genera, 
Erythroxylon, with about 90 species, natives of South America and 
Africa, and Aneulophus, with a single species, A. Africana, a shrub of 
Upper Guinea. The plants are all shrubs or trees with small flowers, 
having 5 sepals and petals, and 10 stamens, the latter monadelphous, 
as we noted those of the Leguminosae to be. The fruit is a drupe con- 
taining a single seed. The bark, as the name indicates, contains a red- 
dish coloring matter, from which a dye is prepared. The most inter- 
esting of the Erythroxylons is undoubtedly #. Coca, which yields the 
‘famous drug known as cocaine (Fig. 125 no. 3). 
Family Zygophyllaceae. Caltrop or Bean-caper Family. Con- 
tains about 20 genera and 150 species, of wide distribution in warm and 
tropical regions. They are herbs, shrubs, or trees, with leaves mostly 
opposite and more or less divided. The flowers are perfect, with the 
parts chiefly in fives; ovary 4-12 celled, capsular or baccate in fruit. 
Several low herbs with pinnate leaves 
and yellow flowers, belonging to the re- 
lated genera Tribulus and Kallstroemia, 
are common in the southwest, as is also 
the interesting creosote bush (Covillea 
Mexicana). So strong is the odor of the 
resinous principle in this plant, that I 
have known herbarium specimens many 
years old to cause a violent attack of hay- 
fever in a person subject to that disease. 
The shrub thrives in the desert region of 
Arizona and New Mexico and Mexico, and 
is very ornamental when in full bloom, 
although valueless either as fuel or for 
Fig. 126. Creosote bush (Covitea forage (see Fig. 126). The genus Guiacum 
Mexicana); flowering branch, one-half consists of trees noted for the remarkable 
Spine) Bes “OnE hardness of their wood, and for the resin 
which they contain. G. officinale, which is highly ornamental in culti- 
vation, with its blue flowers and pinnate leaves, yields the heavy wood 
known as lignum-vitae. The leaves of G. sanctum are frequently used 
in the West Indies as a substitute for soap. 
The seeds of several Old World shrubs or herbs belonging to this 
family, notably Zygophyllum Fabago, the bean caper, and Peganum Har- 
mala, are used as vermifuges. 
Family Cneoraceae. Cneorum Family. Contains the single genus 
Cneorum, comprising about 12 species of maritime shrubs in the Medi- 
terranean region and in the Canary Islands. They have yellow flowers 
with 3-4 petals, 3-4 stamens, and a 3-4-lobed ovary. The fruit is pecu- 
