THE AGAVES OF LOWER CALIFORNIA. 61 
The distributional remarks under A. dentiens pertain also 
to this species. 
Agave Nelsoni Trelease. 
A. Shawii Nelson, Nat. Geogr. Mag. 22: 449, 451. ff 1911. 
Cespitose, acaulescent. Leaves smooth, glaucous, lance-oblong or 
ovate-oblong, little acuminate, openly concave, about 7X 18-35 cm., stiffly 
erect-spreading: spine straight, half-conical, dull grayish or blackish, 
5 30mm., very openly grooved to the upper third, decurrent for 
about its own length: prickles fragile and easily detachable, fading 
from dull brown, 10-20 mm. apart, about5 mm. long, broadly triangu- 
lar, lightly curved, especially upwards. Inflorescence 3-8 m. high, 
paniculate only at the top: scape slender: bracts rather distant, ap- 
pressed: branches few, short, ascending or upcurved, tripartite: pedi- 
cels about 5 mm. long. Flowers light yellow, cup-shaped, 40-50 mm. 
long: ovary 20-30 mm. long, fusiform: tube extremely short, 2-3 mm. 
deep; segments rather elliptical, 4-7 15-17 mm., decidedly shorter 
than the ovary: filaments inserted on the outer part of the nearly flat 
floor of the tube, 30-85 mm. Icng and twice as long as the segments. 
Fruit? 
North-central Lower California, at an altitude of 1400- 
1800 feet.—Nelsoni, E. W. Nelson, one of the most expert 
field students of the geographic distribution of North Amer- 
ican animals and plants—Map (V). Pl. 65-67. 
Specimens examined:—San Fernando (Nelson and Gold- 
man, 7111, Sept. 4, 1905,—the type). Onyx (Nelson and 
Goldman, 7117, Sept. 7, 1905,—with more elongated leaves 
and larger flowers, on which, perhaps, it is differentiable). 
AGAVE DATYLIO Simon, Cat. [1900]: 15,— name only.— 
Weber. Bull. Mus. Hist. Nat. 8: 223. 1902. 
Agave sp. Brandegee, Proc. Cal. Acad. ii. 3:174, 227. nos. 581, 
729. 
Cespitose, acaulescent. Leaves yellowish gray-green, smooth, 
oblong-lanceolate, channeled above, 3-4 30-75 cm., fleshy, rigid: 
spine nearly straight, stoutly triquetrously conical, from glossy pur- 
plish brown becoming blackish or gray, 4-6 X 20-30 mm., little decur- 
rent, very shallowly and openly grooved near the base: prickles from 
glossy chestnut becoming dull grayish brown, 20-30 or even 50 mm. 
apart, 3-5 mm. long, triangular and mostly recurved from heavy or 
lenticular bases or the narrowed cusps lacking. Inflorescence 4-5 m. 
high, lightly glaucous, the slender scape branches moderately short- 
