387 
12. Cereus pectinatus spinosus, nom. nov. 
Cereus pectinatus armatus Poselger, Allg. Gart. Zeit. xxi, 134 (1853), not Cereus 
armatus Otto. 
Ribs 15 or 16: radial spines 16 to 20; central solitary and longer than 
the radials.—Type unknown. 
Near Monterey, Nuevo Leon. 
13. Cereus adustus Engelm. P1. Pend]. 50 (1849). 
Echinocereus adustus Engelm. Wisliz. Rep. 20 (1848). 
Ovate, 4 to 10 em. high, 2.5 to 5 cm, in diameter: ribs 13 to 15, with 
oval approximate areolie: radial spines 16 to 20, appressed, white with 
dark tip, the 4 or 5 upper short (2 mm.) and setaceous, the lateral and 
lower longer (8 to 101mm. and 4mm.) and stouter; centrals none: flower 
and fruit unknown.—Type, Wislizenus of 1846, in Herb. Mo. Bot. Gard. 
In the mountains of Chihuahua, in ‘“ Cosiluiriachi.” 
Specimens examined: CHUIUAHUA (Wislizenus of 1846 in part). 
This species is distinguished from its allies by its fewer ribs, broader areoliv, low- 
est spines much as in pectinatus, and no centrals, 
14. Cereus adustus radians (Kngeli.). 
Echinocereus radians Kngelm. Wisliz. Rep. 20 (1848). 
Upper radials 2 to 4 mm. long, lateral 10 mm., lower 6 min. ; central 
solitary, much stouter, porrect, brown or black, 2.5 em, long.—Type, 
Wislizenus of 1846 in Herb, Mo. Bot. Gard. 
In the mountains of Chihuahua, in ‘* Cosihuiriachi.” 
Specimens examined: CHuivuanua (Wislizenus of 1846 in part). 
+ ++ Central spines & to 50 mm, long. 
15. Cereus roetteri Engelm. Cact. Mex. Bound. 33 (1859), 
Cereus dasyacanthus minor Engel. Syn, Cact. 279 (1856). 
Ovate-cylindrieal, 12.5 to 15 em. high: ribs 10 to 13, tuberculately 
interrupted, with areole 8 to 12 mm. apart: spines subulate from a 
bulbous base, reddish with dark tip, at length ashy, 8 to 16 mm, long; 
radials 8 to 15 (often setaceous ones added above), lateral longer (lower 
10 to 16 mm., upper 4 to 6 mm.), lowest spine shorter; centrals 2 to 5, 
stouter, often somewhat shorter, usually 5 to 12 mm. long (rarely one 
longer): flowers purplish-red, 6 to 7.5 cm, long: fruit subglobose, 16 to 
290 mm. long: seed obliquely obovate, strongly and irregularly tubereu- 
late, 1.4mm. long. (7/1. Cact. Mex, Bound. t. 41, f. 3-5)—Type, Wright 
of 1851 and 1852 and Bigelow of 1852 in Herb. Mo. Bot. Gard. 
From the region about E1 Paso, Texas, southward into Chihuahua and 
westward into Arizona. 
Specimens examined: TEXAS (Wright of L8oL and 1852; Briggs of 
1892): ARIZONA (Lemmon of 1881): CHIHUAHUA (Bigelow of 1852). 
16. Cereus rufispinus Engelm. Pl. Fendl. 50 (1849), 
Echinocereus rufispinus Engelm. Wisliz. Rep. 20 (1848). 
Ovate-cylindrical, 10 em. high and 5.5 cm. in dameter: ribs 11, with 
approximate areole: radial spines 16 to 18, interlocked and at length 
