STANDLEY TREES AND SHRUBS OP MEXICO. 887 



ovary bearing long brown deciduous bristles, especially from the upper 

 areoles. 



Opuntia cliaetocarpa Griffiths^ is perhaps the same species. 0. zacuapanensis 

 Berger * is closely related. 



78. Opuntia hyptiacantha Weber, Diet. Hort. Bois 894. 1898. 

 Opuntia nigrita Griffiths, Rep. Mo. Bot. Gard. 21: 169. 1910. 

 lOpuntia cretochaeta Griffiths, Proc. Biol. Soc. Washington 29: 11. 1916. 

 Oaxaca. 



A tall much-branched plant ; joints oblong to obovate, 20 to 30 cm. long, 

 pale green, but when young bright green ; spines on young joints single, 

 porrect, and accompanied by 2 or 3, sometimes many, white, slightly pungent 

 hairs; spines on old joints 4 to 6, somewhat spreading or appressed, 1 to 2 

 cm. long ; glochids few, brownish ; areoles small, 1.5 cm. apart ; leaves small, 

 brownish ; flowers red ; fruit globular, yellowish, its areoles filled with long 

 weak glochids ; umbilicus broad, only slightly depressed. 



Opuntia chavena Griffiths' is perhaps the same species. It is said to be 

 known in Aguascalientes as " nopal cadillo," " nopal chaveiio," and " nopal 

 cascaron." 



79. Opuntia streptacantha Lem. Cact. Hort. Monv. 62. 1839. 

 San Luis Potosi and elsewhere in central Mexico. 



Much branched, up to 5 meters high, sometimes with a trunk 45 cm. in diam- 

 eter ; joints obovate to orbicular, 25 to 30 cm. long, dark green ; areoles small, 

 rather close together for this group ; spines numerous, spreading or some of 

 them appressed, white ; glochids reddish brown, very short ; flowers 7 to 9 cm. 

 broad, yellow to orange, the sepals reddish ; fruit globular, 5 cm. in diameter, 

 dull red or sometimes yellow within and without. " Tuna cardona," " nopal 

 cardon." 



This is one of the most important economic Opuntias of Mexico. It has 

 sometimes been reported as O. cardona, a name which has never been properly 

 I-ublished. 



Optmtia pachona Griffiths^ is closely related and perhaps only a form of this 

 species. 



80. Opuntia amyclaea Ten. Fl. Neap. Prodr. App. 5: 15. 1826. 

 Doubtless native of Mexico, but not known in the wild state. 



Erect; joints oblong to elliptic, 30 to 40 cm. long, about twice as long as 

 broad, thick, dull green, a little glaucous ; areoles small, with 1 or 2 short 

 I'ristles from the lower parts of areoles; spines 1 to 4, stiff, nearly porrect, 

 i^sually less than 3 cm. long, white or liorn-colored, the stoutest angled; glochids 

 brown, soon disappearing ; flowers yellow ; fruit yellowish red, not very juicy. 



81. Opuntia megacantha Salm-Dyck, Hort. Dyck. 363. 1834. 

 Opuntia castillae Griffiths, Rep. Mo. Bot. Gard. 19: 261. 1908. 

 'iOpuntia incarnadilla Griffiths, Rep. Mo. Bot. Gard. 22: 27. 1912. 

 Much cultivated in Mexico. 



Plants tall, 4 to 5 meters high or more, with a more or less definite woody 

 ( runk ; joints of large plants obovate to oblong, often oblique, sometimes 40 to 60 

 cm, long or more, pale dull green, slightly glaucous ; areoles rather small, on 



^Proc. Biol. Soc. Washington 27: 25. 1914. 

 "Hort. Mortol. 413. 1912. 

 'Rep. Mo. Bot. Gard. 19: 264. pi. 23. 1908 

 *Rep. Mo. Bot. Gard. 21: 168. pi. 22. 1910 



