OPUNTIA. 169 



come from Mexico. From the description it may belong to our series Dillenianae, but we 

 are unable to associate it with any species known to us; the ovary is described as com- 

 pressed and tubercled. 



OpunTia anahuacEnsis Griffiths, Bull. Torr. Club 43: 92. 1916. 



A low, reclining or prostrate plant, up to 5 dm. high, 1.5 meters broad; joints obovate, glossy, 

 yellowish green, 27 cm. long,. 13 cm. broad; spines yellow or becoming white, i or 2, porrect, flattened, 

 twisted, 2 or 3 cm. long; flowers yellow; style white; stigma-lobes 6, white; fruit dark purplish red, 

 pyriform, 7 cm. long. 



Type locality: Anahuac, Texas. 



Distribution: Known only from the type locality, at the mouth of Trinity River, 

 eastern Texas. 

 Opuntia megalanTha Griffiths, Bull. Torr. Club 43: 530. 1916. 



A tall, erect, open-branching plant, 2 meters high or more; joints obovate, glaucous, grayish 

 green, 21 cm. long, 14 cm. broad; spines yellow, i to 3, or even 5 or 6 on old wood, the longest often 

 4 to 5 cm. long; flowers yellow, 10 to 11 cm. in diameter; petals 5 cm. long, obovate; style white; 

 stigma-lobes 8 or 9, white or tinged with green; fruit dark red. 



Known only from cultivated plants received from the Berlin Botanical Garden, where 

 it was grown as Opuntia bergeriana. 



Series 16. MACDOUGALIANAE. 1 a 



Erect, mostly tall species, with flat, broad, ^ -^ \^ #^ 



and thin, persistent joints, the epidermis, at least ^^^^^ !^ ^**~ 



that of the ovary, pubescent or puberulent. The ~^ ~^ P 1 Hr 



spines, when present, yellow. There are about O^^ W ^ 



half a dozen species, natives of central and /^ ' ty y / 



southern Mexico. ^T W «^ \ 3/ '^ 



Key to Species. -^ j -x~ ^ 



Joints merelj' finely puberulent or ^^ ^ ^ >(h — T 



glabrous; spines 1.5 cm. long or '^ ^ ^ Of ^ ^ 



less; ovary velvety 184. 0. durangensis •! , . v ^ 



Joints distinctly pubescent; spines 



2 to 3 cm. long. "''^ M •^■^ \ -^ 



Petals red. M ^ /\ • '^ a V^ 



Style shorter than the petals 185. 0. atropes ^^K n 7 V- \" '^^ 



Style as long as the petals. 186. 0. affinis -X/^ ^ ' '^^ rL 



Petals yellow. ^KO ^ y V 



Spines acicular, at first yel- /\ ja 1 A j/y ^J^ 



low, soon white 1S7. 0. macdougaliana \ \ ws ^ I/l 



Spines subulate. «s "%. / \\i A;}^ 



Petals retuse; areoles of \R , -^ S \jV ' /* 



ovary many, approxi- ^\^ ^ ,-j 9~ ' 



mate 188. 0. veliitina ^\ '^ "X \f 



Petals mucronate; are- V ft • 1 i 



oles of ovary few, dis- ^J^-4) ^a> 



tant 1S9. 0. wikoxii ''\.J^ ^ -^.^ 



ix. ^/. T 

 184. Opuntia durangensis Britton and Rose, \ /;i-.n 



Smiths. Misc. Coh. 50: 518. 1908. „ ^ r^ .■ a ■ ^ 



^ ^ ^ Fig. 208. — Opuntia durangensis. X0.4. 



Joints broadly obovate, about 20 cm. long, 

 16 cm. broad, pale green, glabrous or minutely puberulent, bearing numerous areoles; areoles i to 

 2 cm. apart, elevated; spines 3 to 5 at an areole, short, 1.5 cm. long or less, pungent, spreading, 

 yellow, but in age becoming darker ; glochids brown, 2 to 3 mm. long; flowers yellow, 5 cm. long; 

 petals broad, apiculate ; ovary 3 to 4 cm. long, finely pubescent, bearing many areoles with numer- 

 ous glochids and a few spines; fruit white or red; seeds about 3 mm. broad. 



Type locality: Near Durango, Mexico. 

 Distribution: Central Mexico. 



This species was collected by the late Dr. E. Palmer in 191 2, but he did not record 

 the size and habit of the plant. The joints suggest a large, bushy species. 

 Figure 208 represents a joint of the type specimen. 



