266 MISSOURI BOTANICAL GARDEN. 



specimens. The specific name is the common Mexican name 

 applied to this plant. 



The type specimen is no. 8149 D. G., collected near Zaca- 



tecaS; MexicO; September, 1905. 



Opuntia Guerrana sp. nov. 



A suberect or ascending, open branching plant, 9 to 12 dm. high and 

 about the same in diameter; joints oblong obovate to subcircular, thick. 

 heavy, glaucous, blue-grccn, 15-20 cm. by 20-25 cm.; areolcs black, sub- 

 circular to obovate, about 5 mm. in longest diameter; wool tawny; spic- 

 ules yellow, abundant, unequal, on sides and lower portion of edge in a 

 compact crcscentic tuft, 1 to 2 mm. long but around the apex of joint 

 there may be an abundance of them lengthened to 1 or 2 cm. ; spines white 

 or light straw color and translucent at the base but turning a mottled 

 dirty black with age, 1 to 6, mostly 2 to 4, flattened, often twisted, erect, 

 divergent or some of lower in areole somewhat recurved; flower yellow, 

 filaments greenish white, stigma green, fruit subglobose, greenish white, 

 4 to 5 cm. in diameter, with seed variable and much aborted, but mostly 

 large, 4-5 by 5-6 mm., deeply notched, mar^nal thickening prominent, 

 1 mm. wide. 



The species is related to 0. robusta^ but is smaller through- 

 out, with very different fruit. It is known as Nopal tapon 

 or Nopal tapon bianco in some sections. This shows its 



d 



d 



in the field; supplemented by further notes from the dried 

 specimens. It is with pleasure that I dedicate this species 



L. Guerra 



and to whom 



indebted 



of Opuntia. 



The type is no. 8475 D. G., collected near Dublan Hidalgo, 

 Mexico. Seotember, 190G. 



Opuntia discata sp. nov- 



Plant ascending-erect, rather compactly branched, 9 to 15 dm. high 

 and about the same in diameter; joints broadly obovate to subcircular, 

 commonly about 25 by 27 cm., dark green w^hen young, but gray waxy 

 green when mature; leaves about 1 cm. long, subulate pointed, slightly 

 flattened; areoles large, promhient, circular to oval, tawny to brown when 

 young and black in age, 6 to 10 mm. in diameter, much larger on edges of 



