425 
20. Opuntia angustata Engelm. Syn. Cact. 292 (1856). 
Prostrate or ascending, with elongated obovate joints (narrowed 
toward the base and rounded above) 15 to 25 em. long or more and 7,5 
to 10 em. broad: pulvini over 2.5 em, apart, with grayish wool, slender 
yellowish-brown_ bristles, and 2 or 3 (often 1 or 2 weaker ones added 
below) stout angular detlexed spines 2.5 to 5 cm. long, straw-colored or 
white, yellow or red toward the base: fruit obovate subglobose, broadly 
and deeply umbilicate, tuberculate and bristly, reddish, 2.5 to 3.9 cM. 
long: seeds about regular, with broad almost curled margins, 6 min, or 
more in diameter. (JUL. Pacif. R. Rep. iv, t. 7, f. 38, 45 t. 22, f. 11)—Type, 
the Bigelow specimens in Herb. Mo, Bot, Gard. 
From New Mexico to the mountains of southern California. 
Specimens examined: New Mexico (Bigelow of 1853): ARIZONA 
(Bigelow of 1854): CALIFORNIA (Bigelow of 1854). : 
21. Opuntia angustata comonduensis, var, nov. 
Joints semiobovate (one side straight, as if an obovate joint had been 
divided in the median line), tapering below as in the species, but with 
greatest diameter near the middle and tapering above, 20 em. long, 4.5 
to 7.5 em. broad: spines terete: flower 5 cm. long, yellowish, with 
reddish tinge outside: fruit at last neither tuberculate nor spiny, but 
with prominent woolly and bristly pulvini, pyriform, about 4 em. long: 
seeds smaller, 3.5 to 4 mm. broad.—Type in Herb. Brandegee. 
Comondu, Lower California. 
Specimens examined: LOWER CALIFORNIA (Brandegee of 1889). 
The spines are most prominent along the curved margin and above, some pulvini 
becoming spineless, until in one specimen the whole joint is unarmed except 2 few 
pulvini. In his discussion of angustata! Dr. Engelmann remarks that while speci- 
mens east of the Colorado have sharply angular spines, the one that he had from 
the California mountains had spines not so angular, and some of them were almost 
terete. This Lower Californian variety has all the spines distinctly terete. As Dr. 
Engelmann’s description of the fruit was drawn from a single specimen, it is prob- 
able that there was no evidence that the tubercles eventually disappeared, 
C. Spines reddish or blackish. 
22. Opuntia macrocentra Engelm. Syn. Cact. 292 (1856). 
Ascending, 6 to 9 dm. high, with large suborbicular thin often pur- 
plish joints 12.5 to 20 em, long and 10 to 17.5 em. broad: pulvini 2 to 
2,5 em. apart, with grayish wool, slender short yellow bristles, upper- 
most and marginal ones alone armed, the lower without spines: spines 
1 or 2 (rarely more), 5 to 7.5 em. long, straight or variously flexed, reddish- 
black, paler upward, often annulate, upper terete, lower a little shorter 
- and compressed or channelled: flowers yellow, 7.5 cm. broad: fruit ovate, 
3 em. long: seeds much twisted, 4 to 4.5 mm. broad, broadly and obtusely 
undulate margined. (Jl, Cact. Mex. Bound. t. 75, f. 8)—Type, the 
Wright specimens in Herb. Mo. Bot. Gard. 
' Pacif. R. Rep., iv [pt. 1], 39. 
