52 William Trelease: Nolineae novae. 
13. Dasylirion leiophyllum (Engelmaun in herb.) Trelease, l. c., p. 433. 
— Dasylirion sp. Trelease, Pop. Sci Monthly, LXX; 220, f. 14. — 
Shortly caulescent. Leaves becoming 15—20 mm wide, scarcely 1 m 
long, somewhat brush-tipped, green or at first somewhat glaucous, 
smooth, rather glossy: prickles usually 10—15 mm apart, 3—4 mm long, 
yellow, usually becoming orange or red at least above the middle, the 
margin sometimes smooth between them.  Inflorescence rather high. 
Perianth segments scarcely 2 mm long. Fruit obovately subelliptieal, 
4-5 X 6 8 mm, the thick style about equaling the moderately open 
and deep notch or exserted if the wings have not fully developed. Seed 
2 X 3 mm. — PI. 12. — Southern Texas, in the Rio Grande region. 
passing into New Mexico and reaching or reappearing in central 
Chihuahua. — Adjoining or overlapping the range of D. Wheeleri Wis- 
lizeni and Nolina erumpens and affinis, — Specimens examined: Texas. 
Presidio (Havard, 1880, — the type) Eagle Pass (?Havard, 1883). 
Sierra Blanca (Trelease, 1892, 388, 1900; Mulford, 275, 1895; Rose, 
Standley & Russell, 12222, 1910). Van Horn (Eggert, 1900. New 
Mexico. Central (Mulford, 424, 1895). Florida Mountains (Mulford, 
1037, 1895). Chihuahua. Sta. Eulalia Mts. (Pringle, 149, 1885; 
Williamson, 1885). 
14. Dasylirion texanum var. aberrans Trelease, l. c., p. 434. — Differ- 
ing from the type in its dull somewhat glaucous leaves, 15 mm wide. 
Northern Mexico. — Specimens examined: „States of Coahuila and 
Nuevo Leon* (Palmer, 1315, 1880, — the type). 
15. Dasylirion simplex Trelease, l. c, p. 434. —  Acaulescent. 
Leaves 1—10 mm wide, scarcely 1 m long, rather sparsely very long- 
fibrous at tip, green, smooth, glossy: prickles 10—15 or 20 mm apart, 
2—3 mm long, rather straight, prevailingly upcurved, yellow, the upper 
half becoming brown or finally almost black, the margin nearly smooth 
between them. Inflorescence (typically?) small, the staminate with one 
to three small branches to each division and the pistillate simple or its 
divisions with a short basal branch. Fruit broadly obovate, 5—6 X 
7 mm, the thick style about equaling the open moderate notch. Seed 
(immature) 2 X 3 mm. — PI, 12. — North-central Mexico. In the 
region of Nolina durangensis. — Specimens examined: Durango. Tepe- 
huanes (Palmer, 310, 1906, — the type) Santiago Papasquiaro 
(Palmer, 422, 1896). 
16. Dasylirion durangense Trelease, l. c., p. 438. — Habit? Leaves 
20 mm wide, scarcely 1 m long, lightly glaucous, nearly smooth, dull: 
prickles 5—10 mm apart, 2—3 mm long, yellow, with orange tips. In- 
florescence tall. Fruit broadly elliptical-cordate, 7—8 X 9 mm, the thick 
style scarcely half as long as the rather open deep notch. Seed 
2x3 mm. — Pl. 11,12. — North-central Mexico. In the region of 
Nolina durangensis. — Specimens examined: Durango. Durango (Palmer, 
557, 1896, — the type). 
