OPUNTIA. 113 



An Opitntia collected by H. Pittier in Costa Rica and now growing in the cactus house 

 of the U. S. Department of Agriculture has not been identified. It resembles somewhat 

 Opuntia tnacantha, but is much out of the range of that species and differs from it in some 

 important respects. The joints are small, obovate to oblong, rounded at apex, dark green 

 with purple blotches below the areoles, with low, broad tubercles; margin of the areole 

 bearing short white hairs; spines usually wanting, but cultivated specimens bear a single 

 short spine 6 to 7 mm. long from an areole. 



FIG. 140. Opuntia triacantha. 



101. Opuntia jamaicensis Britton and Harris, Torreya n: 130. 1911. 



Erect, i meter high, with a short subcylindric trunk; branches several, ascending, joints dull 

 green, obovate, much narrowed at base, flat, rather thin, readily detached, 7 to 13 cm. long, 5 to 

 7.5 cm. wide; areoles about 2.5 cm. apart; spines i to 5, usually only 2, acicular, unequal, white, 

 2.5 cm. long or less; flowers 4 cm. broad; petals 16 to 18; filaments greenish white; style white; 

 stigma-lobes 7 or 8, creamy white; fruit pyriform, red, 3.5 to 4 cm. long; seeds 4 mm. broad. 



Type locality: St. Catherine, Jamaica. 



Distribution: Plain south of Spanish Town, Jamaica. 



The following figures are from paintings by Miss H. A. Wood: 



Plate xvin, figure 4, shows a fruiting joint; figure 5 is of a section of the fruit; plate xix, 

 figure i, shows the type plant about one-third natural size; figures 2, 3, and 4 are of the 

 flowers ; figures 5 and 6 show the stamens ; figure 7 represents the style. 



101(7. Opuntia guatemalensis sp. nov. (See Appendix, p. 218.) 



102. Opuntia tuna (Linnaeus) Miller, Card. Diet. ed. 8. No. 3. 1769. 



Cactus tuna Linnaeus, Sp. PI. 468. 1753. 

 Cactus humilis Haworth, Misc. Nat. 187. 1803. 

 Opuntia humilis Haworth, Syn. PI. Succ. 189. 1812. 

 Opuntia polyantlia Haworth, Syn. PI. Succ. 190. 1812. 

 Cactus polyanthos Sims, Curtis's Bot. Mag. 53: pi. 2691. 1826. 

 Opuntia multiflora Nicholson, Diet. Card. 2: 503. 1885. 



Plants 6 to 9 dm. high or less; joints usually small, but sometimes up to 16 cm. long, obovate 

 to oblong, light green, except above the areoles and there brownish; leaves minute, fugacious; areoles 

 arge; spines 2 to 6, usually only 3 to 5, slightly spreading, light yellow; glochids yellow; flowers about 

 5 cm. broad; sepals orbicular, yellowish, with a purple stripe along the center; petals light yellow, 



