-v 



BRITTON AND ROSE] OPUNTIOIDEAE OE NORTH AMERICA 523 



OPUNTIA POLLARDI Britton & Rose, sp. nov. 



Apparently prostrate and most nearly related to Opuntia opuntia; 

 joints obovate, pale green in dried specimens, about 10 cm. long, 

 6 cm. wide, and apparently less than I cm. thick; areoles 1.5 to 3 

 cm. apart, bearing numerous brown glochides 2 to 3 mm. long, 

 those toward the top of the joint each with a single stout stiff pun- 

 gent spine 2.5 to 4 cm. long; fruit short-obovoid, 2.5 cm. long, 1.5 

 cm. thick, with a few areoles bearing tufts of brownish wool but 

 no spines and but few glochides; seeds 4 to 5 mm. wide, much 

 thicker than those of 0. opuntia. 



Biloxi, Harrison County, Mississippi, August 1, 1896, C. L. Pol- 

 lard (no. 1 138). Type in herbarium of New York Botanical Garden. 



OPUNTIA MACRORHIZA Engelm. 



Opuntia macrorhiza Engelm. Bost. Journ. Nat. Hist. 6:206. 1850. 

 Opuntia mesacantha macrorhiza Coult. Contr. Nat. Herb. 3:430. 1896. 



Type locality : Rocky places on the Upper Guadalupe, Texas. 

 Distribution : Kansas to Texas. 



Illustrations: Pac. R. Rep. 4: pi. 12. figs. 7, 8; pi. 23, fig. 6; W. 

 Watson, Cactus Cult. figs. 82, 83; Forst. Handb. Cact. ed. 2. fig. 127. 



OPUNTIA AUSTRINA Small 



Opuntia austrina Small, Fl. SE. U. S. 816. 1903. 



Type locality: Miami, Florida. 

 Distribution : Florida. 



OPUNTIA GREENEI (Coult.) Engelm. 



Opuntia mesacantha greenei Coult. Contr. Nat. Herb. 3:431. 1896. 



Type locality : Golden City, Colorado. 



Distribution : Colorado to Arizona. 



This species is clearly distinct, but has never been formally given 

 specific rank, although long ago indicated as deserving it by Dr. 

 Engelmann in manuscript. 



OPUNTIA STENOCHILA Engelm. 



Opuntia stenochila Engelm. Proc. Am. Acad. 3:296. 1856. 



Opuntia mesacantha stenochila Coult. Contr. Nat. Herb. 3:430. 1896. 



Type locality : "Canyon of Zuni," New Mexico. 

 Distribution: Western New Mexico and Arizona. 

 Illustrations : Pac. R. Rep. 4 : pi. 12. figs. 4-6; pi. 23. fig. p. 



