98 MISSOURI BOTANICAL GARDEN. 
Y. Scnortir Engelmann, Trans. Acad. St. Louis. 8:46. 
(1873).— Watson, Proc. Amer. Acad. 14: 252. — 
Baker, Journ. Linn. Soc. Bot. 18 : 228. — Trelease, 
: Rept. Mo. Bot. Gard. 4:185. pl. 3.— Sargent, Silva. 
10:17. pl. 501.— In part. 
Y. macrocarpa Engelmann, Bot. Gazette. 63224. (1881). 7:17.— 
Baker, Kew Bull. 18928. —Trelease, Rept. Mo. Bot. Gard. 8 3 162. 
pl. 46. 
? ¥. Mazeli Chabaud, Belg. Hort. 1882; 222.— Wiener Ill. Garten- 
Zeit. 11; 347. Baker, Kew Bull. 189238. 
Arborescent, rarely over 3 or4 m. high, simple or few branched above. 
Leaves blue-green, smooth, rather rigidly divergent, thin, concave, pun-- 
gent, 20 to 40 mm. wide, very finely and often sparingly filiferous. In- 
florescence densely panicled close to the leaves, very tomentose or rarely 
nearly glabrous. Flowers subglobose. Fruit oblong, mostly large: 
seeds 7X 9 mm. — Plates 55. 85, f. 1. 
Southern Arizona, especially about Benson and Nogales, 
and as far into the Mexican state of Chihuahua at least as 
Colonia Garcia. Flowering in late summer. — Plate 96, 
i: i & 
When, in 1882, Dr. Engelmann described fuller material 
of the Arizona Yucca which he had named Y. macrocarpa 
the year before, he was so impressed with the resem- 
blance of its tomentose panicle to the fragments of inflo- 
rescence in the Torrey herbarium accompanying the leaves 
of what he had called Y. Schottii, that he suggested that 
the latter might possibly be only a short-leaved form of 
the same species. This suggestion has been adopted by a 
number of recent writers, who, irrespective of a prior use 
of the name macrocarpa in the genus, have come to look 
upon Y. macrocarpa Engelm. as a synonym of Y. Schottii. 
This Y. Schottit of recent writers is abundant to the west 
and northwest of Nogales, as far, at any rate, as the vicin- 
ity of Benson and the Pajarito mountains, and there be- 
comes a small tree two or three meters high, most frequently 
unbranched ; and it is especially marked among the Yuccas 
of the region by the bluish-green color and thinness of its 
smooth concave finely filiferous brown-margined leaves, and 
