42 : BOTANY. 
small extent soluble in water, and the solution has an acid reaction. It 
yields a light yellow precipitate with acetate of lead. The part of the alco- 
holic extract that is insoluble in water is easily soluble in alkalies. It also 
dissolves in nitric acid at a moderate heat, whereby oxydation takes place. 
On addition of water, a yellow, brittle mass is precipitated.” The Mexi- 
cans are said to use an infusion of the leaves for bathing in, in rheumatic 
affections. See Vol. III, Wheeler’s Reports, pp. 608-9. 
Rus piversitosa, T.& G. Poison Oak, Yeara.—Much like our poison 
_ oak of the Eastern States. Common on the Pacific coast. For remedy see 
Grindelia robusta. 
NEGUNDO AcERoIDES, Mcench. Box-Elder—Bearing in mind the great 
success of the experiments with this tree in Kansas and Nebraska, and its 
wide range over the more arid areas of our Southwest, it may be well to 
remember it in further attempts at tree culture. Though hardly to be 
considered as a valuable timber, it may fairly be reckoned on the shade 
and fuel list, and fairly associated in this respect with the following: 
ScHInus MOLLE, Linn., from Mexico and South America.—Now 
grown in Southern California under the name of Pepper Tree and Chili 
Pepper. 
Prosopis suLirtora, DO. Mesquit. Algaroba of the Mexicans.—Grows 
from Southeastern California east to Texas, where it attains the tree size, and 
forms dense thickets; extends south into South America. The gum exud- 
ing from this tree closely resembles gum arabic in appearance and in its 
properties, and may some day become an important article in trade. The 
pods while yet in pulpy condition are a valuable forage, eagerly eaten by 
animals, and on which they actually thrive while making hard marches. 
The beans contain thirty per cent. of grape-sugar. Dr. Loew asserts that 
the Comanche Indians prepare an alcoholic beverage from them. As a 
fuel it ranks with the hickory of the Eastern States, and the charcoal made 
from it is said by Dr. Loew to be of the best quality for metallurgical and 
smelting purposes. Besides this species, there is another, hardly less useful, 
i. €., P. pubescens, Benth., the Screw-Beay, the pods of which are ground 
into flour by the Indians. The wood of both species is of great value in 
some of the arts. 
