1885.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 515 



Posts of Guayacan are said uever to decay, and therefore must be of 

 much value for fencing-. The bark of the roots, ground, possesses 

 stroug detergent properties and is reputed excellent to wash woolen 

 fabrics. 



RUTACEiE. 



Xanthoxylum Clava-Herculis, L. A'. CaroUnianum, Lam. (Prickly Ash; Tooth- 

 ache-Tree.) 



Prickly shrub, with pinnate leaves ; common on banks of streams. 



Xanthoxylum Pterota, HBK. (Colima.) 



Very common shrub on the Lower Eio Grande; distinguished from 

 the preceding by the winged-margined petioles and smaller leaflets. 

 Wood yellow, dense, exceedingly hard and heavy. 



The bark, leaves and fruit of these two species are very pungent and 

 acrid, causing a strong and lasting tingling sensation in the tongue 

 and lips, followed by partial numbness. The former is officinally used 

 in decoction as an arterial and nervous stimulant. The leaves of both, 

 chewed, are an effective sialogogue. 



Helietta parvifolia, Benth. (Barreta.) 



Shrub common on the bluffs of the Lower Eio Grande, apparently 

 only good for fuel. 



Ptelea trifoliata, L. (Hop-Tree.) 



Shrub or very small tree* on the San Antonio Eiver and other streams 

 of Western Texas. 



Ptelea angustifolia, Benth. 



Shrub said to occur on the Lower Eio Grande ; probably rare. 



SIMARUBEiE. 



Castela erecta, Turpin. (Goat Bush ; the Amargoso of the Mexicans.) 



Stiff, branchiug, prickly shrub, 3 to 5 feet high, common on the grav- 

 elly bluffs of the Lower Eio Graude from Eagle Pass downward. An 

 excellent hedge-plant for high and rocky places. 



The bark is intensely bitter and probably contains tannin and some 

 principle akin to quinine. Its decoction is used by Mexicans as an 

 astringent, tonic, and febrifuge. The remarkable properties of this 

 bark, and perhaps of the wood, seem to warrant fuller investigation. 



Kceberlinia spinosa, Zncc. (J unco.) 



Very curious shrub, destitute of apparent foliage, the green, stiff, very 

 intricate branches all tapering into thorns. Common in Western and 

 Southern Texas from El Paso to Brownsville. On the Lower Eio Grande 

 it becomes arborescent. Makes quite formidable hedges. 



Wood of a very deep brown color, resinous, hard and heavy; it burns 

 with a bright blaze, giving off intense heat and a disagreeable smell. 



