2l8 



THE CACTACEAE 



96 a. Opuntia discolor sp. nov. (See page 109, ante.) 



A low plant, forming small dense clumps; joints slender, 4 to 12 cm. long, 1.5 to 2.5 cm. in 

 diameter, turgid, glabrous, dark green with dark purple blotches extending downward from the 

 under margin of the areoles; spines i to 6, acicular, nearly porrect, somewhat variegated but mostly- 

 brown, 3 cm. long or less; glochids tardily developing but conspicuous on old branches, dark brown; 

 flowers light yellow to orange-yellow, only 3 cm. long including the ovary; filaments white; style and 

 stigma-lobes nearly white; fruit evidently very small, bright red. 



Fig. 282. — Opuntia discolor 



from 



Estaro, Argentina, February 23 (type), and No. 

 95, from gravelly hills near Tapia, Tucuman, 



made by Dr. J. A. Shafer in 191 7 which 

 [II, from sandy thickets, Santiago del 



February 



common in dry 



growing best under bushes where it is least dis- 

 turbed. The joints easily become detached, 

 sticking readily to any disturbing object. 



from Opuntia 



more 



from 



plant; figure 284 represents a joint of the plant 



m near lapia. Tucuman 



101 a. Opuntia guatemalensis sp. nov. (See page 



113, ante.) 



Fig, 283. — Opuntia 

 pestifer. Xo. 5. 



-^ 



Fig. 284. — Opuntia discolor 



Low, spreading plant, resembling O. decumbens, but joints glabrous and shining- ioints deeo 

 green sometimes with dark blotches below the areoles; areoles small, filled with brown wool sub 

 tended by small leaves; spines i to 3 at the areoles, terete, acicular, shining white with blackish tips 



smalirthaS' t^Z o^f'^' T^'^y ^"''^^i somewhat spreading; flower-buds reddish; flower much 

 smaller than those of O. decumbens; petals lemon-yellow, 2.5 cm. long; stigma-lobes cream-colored. 



Guatemala 



Wilcox 



ton and flowered there in April 191 5. 



Living specimens 



surgeon on a ship plying 

 sent directly to Washing- 



Figure 285 represents a joint of the type specimen 



