OPUNTIA. 



123 



yellow to orange, 4 to 5 cm. long including the ovary; petals obovate, 2 to 2.5 cm. long; filaments 

 greenish white, short, i cm. long; style 1.5 cm. long, thick, bulbous just above the base; stigma- 

 lobes 5, deep green; ovary globular, 1.5 cm. in diameter, umbilicate, with large areoles; fruit, accord- 

 ing to field observation of Dr. Griffiths, bright red. 



Type locality: About Presidio del Norte, on the Rio Grande. 



Distribution: Texas and northern Mexico. 



This species seems much less common than 0. microdasys, with which it is often con- 

 fused. The joints are gray or bluish green, and the glochids are brown. It does fairly well 

 under greenhouse conditions. 



Illustration: Rep. Mo. Bot. Gard. 20: pi. 3; Carnegie Inst. Wash. 269: pi. 11, f. 94. 



Figure 153 is from a photograph of a plant brought from Mexico for the New York 

 Botanical Garden in 1896 by Mrs. N. L. Britton. 



Fig. 154. — Opuntia pycnantha. Along the coastal plain of Lower California. 



113. Opuntia pycnantha Engelmann in Coulter, Contr. U. S. Nat. Herb. 3: 423. 1896. 



Opuntia pycnantha margaritana Coulter, Contr. U. S. Nat. Herb. 3: 424. 1896. 



Often low and creeping, but sometimes forming a clump 2 dm. high ; joints oblong to orbicular, 

 often 20 cm. long, puberulent or papillose, usually nearly hidden by the thick mass of spines; areoles 

 large and closely set, the upper part filled with yellow or brown glochids, and the lower part with 8 

 to 12 yellow or brown reflexed spines 2 to 3 cm. long; leaves and flowers unknown; fruit 4 cm. long, 

 very spiny; seeds 2 cm. broad, very thick. 



Type locality: Magdalena Bay, Lower CaHfornia. 



Distribution: Southern Lower California. 



Coulter's variety margaritana is known only from Margarita Island, while the species 

 proper is known only from an adjacent island, Magdalena. They differ only in the color 

 of their spines and glochids. Both have been in cultivation in New York City and Wash- 

 ington, but are not weU suited for indoor plants. 



This species grows in one of the driest parts of Lower California on islands where there 

 is no surface water and where there is no rain sometimes for five or six years. 



Figure 154 is from a photograph taken by Dr. Rose near Santa Maria Bay, Magda- 

 lena Island, Lower California, in 191 1. 



