VI. 
PAPERS ON YUCCA, AGAVE, ETC. 
I. YUCCA AND HESPERALOE. 
From Watson’s BoTANy OF THE FortreTH PARALLEL. — REporRT oF THE Unitep STATES GEOLOGICAL EXPLORATION OF THE 
FortTieETH PARALLEL. CLARENCE KING, GEOLOGIST IN CHARGE. V. SUPPLEMENT, 496-497. WasHINGTON, 18 
The following addition to the Catalogue of the plants of Nevada and Utah is from Dr. GrorcE 
ENGELMANN as a result of his recent study of our hitherto ill-defined and little understood species of 
these genera. —S. W. 
YUCCA, L. 
Perianth cup-shaped, of six (whitish) petal-like lance-oval acutish leaves, withering-persistent, longer than the 
six club-shaped filaments. Stigmas 3, more or less united. Pod oblong or cylindrical, somewhat 6-sided, 3-celled, the 
cells incompletely 2-celled by a partition from the back. Seeds very numerous, he horizontal, in 6 rows, black, with 
‘the linear straight or curved embryo diagonal, as long as the albumen. — Stems woody, fibrous, very short or rising 
into thick columnar palm-like simple or branching trunks, bearing persistent rigid linear or lance-linear mostly sharp- 
pointed leaves, with smooth, rough, or filamentose edges, and terminated by an ample compound panicle (or rarely a 
spike) of showy pendulous flowers, opening wide in the evening and half-closed in the morning 
§ 1. EU-YUCCA. Filaments club-shaped, obtuse, papillose-pubescent, mostly shorter than the pistil, often 
spreading or recurved ; anthers oblong or sagittate ; ovary prismatic or subcylindric, obtuse or narrowed into 
a sort of style ; stigmas elongated, bi-lobed, papillose. 
* Sarcocarpa. Pendulous fruit fleshy and indehiscent ; thick seeds somewhat rugose, with deeply lobed 
(ruminated) albumen. 
1. Y.. pacoata, Torr. . Bot. Mex. Bound. 221. Stems none, or short, or several feet high ; leaves very thick 
and rigid, lance-linear, narrowed above the broad base, concave, terminating in a stout spine, with very coarse mar- 
ginal fibres ; flowers panicled; petals rhombic-ovate (1}-14 inches long) or linear-lanceolate (sometimes over 3 inches 
long) ; ovary attenuate into a style ; stigmas short ; fruit ovate or cylindric, long-rostrate. — From New Mexico and 8S. 
Colorado, through S. Utah, to Arizona, California, and Mexico. Northward a low plant, it becomes a tree farther 
south ; leaves 1}-2 feet long, 1}-2 inches wide. The edible sweet fruit are often called “Dates;” seeds variable in 
size, mnciblie the langedt j in the genus, 5-6 lines wide, 14-14 lines thick. 
* « Clistocarpa. Fruit indehiscent, at last dry ; seeds thickish, smooth, with the albumen entire. 
2. Y. BREVIFOLIA, Eng. (Y. Draconis, var. arborescens, Torr. Bot. Whipp., Pac. R. R. Surv. 4. 147). Tree-like, 
at last much branched ; the short narrow leaves crowded at the end of the branches, thick, very rigid, stout, and sharp- 
pointed, not narrowed ahs the broad base, serrulate on the margin; panicle sessile at the end of the branches ; 
fruit large, 4 inches long, ovate, pointed. — Deserts of S. Utah theodieh Arizona to S. E. California where it forms entire 
forests on the desert plateaus at 2-4,000 feet altitude. Often 20-30 feet high and 1-2 feet in diameter, with a thick 
rough bark ; leaves 4-6 inches or in younger specimens"10-12 inches long, 3-}-inch wide, stiffer and stouter pointed than 
any other in the genus. The flower when known may make it necessary to remove it from § Eu-yucca. 
* * * Chenocarpa, Erect fruit dry, septicidally 3-valved from the apex, the valves at last again divided at tip 3 
seed very thin, smooth, with an entire albumen. 
3. Y.anGustiroita, Pursh. Stems none or short; leaves narrowly linear, scarcely narrowed above the broad 
base, rigid, spiny-pointed, nearly flat above, convex below, with very slender marginal fibres, 14-24 feet long ; flowers 
