44 PROCEEDINGS OF THE AMERICAN ACADEMY 



Bursera Hixdsiana, Benth. & Hook. A scrubby bush, 8 feet 

 high, the leaves simple or 3-foliolate upon the same plant: seed black 

 at base, covered above with a hard salmon-colored arillus. The bark 

 is much used for tanning, giving a reddish brown color. Los Angeles 

 Bay. (572.) 



Bursera laxiflora. A small tree with a trunk from 6 inches 

 to a foot in diameter : leaves pinnate, sparingly pubescent, the pubes- 

 cence short and mostly spreading ; rhaehis narrowly winged ; leaflets 

 2 to 4 pairs, thin, ovate to oblong, mostly obtuse, entire or usually 

 with 1 to 4 (rarely 6) blunt teeth, 3 to 9 lines long : peduncles axil- 

 lary, solitary, very slender, 1 to 4 inches long. 1-3-flowererl. and often 

 with 1 to 3 simple foliacpous bracts; pedicels about 6 lines long: 

 sepals narrow, nearly a line long : fruit obovate, narrowed at base, 

 somewhat compressed, 2-valved, 4 lines long. — " Copal " ; in ravines 

 about Guaymas. (280.) 



Bursera fubescens. A tree 10 to 15 feet high, with stout trunk 

 and branches : leaves finely pubescent, pinnate, the rhaehis not winged, 

 1 or 2 inches long; leaflets 4 or 5 pairs, rather thick, oblong-elliptic 

 and entire, 2 to 4 lines long, obtuse, the terminal one cuneate-obovate 

 and crenately toothed or lobed : flowers and fruit unknown. — Evi- 

 dently a Bursera, but unlike any known species in its foliage. "Wood 

 brittle and bark deciduous in broad thin flakes. Plains and stony 

 ridges about Los Angeles Bay. The bark is exported to Europe for 

 tanning. (585.) 



Maytenus phtllanthoides, Benth. A low bush or small tree 

 in sandy and alkaline soils. Muleje and Guaymas. (30.) 



Ziztphus ltcioides, Gray, var. canescens, Gray. A small tree, 

 10 feet high. In sandy bottoms about Muleje and Guaymas. (29.) 



Ziztphus Sonorensis. A small tree with a trunk 5 to 8 feet 

 high and G to 10 inches in diameter, with smooth grayish bark and a 

 compact top, the short rigid branches very thorny: leaves nearly 

 glabrous, thin, ovate to ovate-elliptical, obtuse or retuse, subcuneate 

 to slightly cordate at base, entire or slightly toothed, 1 or 2 inches 

 long with petioles 2 lines lon^: panicles short, finely pubescent, axil- 

 lary and terminal: fruit subglobose and reddish brown when ripe, 

 about 5 lines long, edible, the pedicel 2 lines long : putamen oblong- 

 obovate. 2-celled, 2-seeded, 4 lines long. — Common about Guaymas, 

 near brackish water. (124, 659.) 



Colubrina GLABRA. A compact shrub, 5 or G feet high, unarmed, 

 glabrous or very nearly so: stipules subulate, rigid, deciduous; leaves 

 mostly fascicled, oblong-ovate to elliptical or obovate, obtuse or retuse, 



