OPUNTiA. 



49 



relationship, however, is not shown in the La Mortola plant. With only a very meager 

 description published and no type specimen preserved, it is difficult to decide the relation- 

 ship of this species. No exact type locality is cited for it, but it is said to grow "among 

 rocks, especially towards the west coast, and in the more central portions" of Lower Cali- 

 fornia, where it was first collected by W. M. Gabb in 1867. 



We refer this species with hesitation to the series Leptocaules. 



Opuntia tcnajo (Just's Bot. Jahresb. 24- : 380. 1896) is doubtless an error in spelling 

 for 0. tesajo. 



FIG. 59. Opuntia caribaea forming dense thickets. 



5. Opuntia caribaea sp. nov. 



Stems i to 3 meters high, forming thickets in open woods and waste grounds; ultimate joints 

 horizontal, 5 to 10 cm. long, much thicker than in O. leptocaulis, with short, elevated tubercles; 

 areoles large, bearing white wool and a few long caducous hairs; spines i to 3, porrect, acicular, 

 2 to 3 cm. long, covered with thin, brown, papery sheaths; glochids dark brown; leaves small, i to 

 2 mm. long, acute; flowers not known; fruit red, 1.5 to 2 cm. long, usually naked but sometimes 

 bearing short spines from the upper areoles, so far as known always sterile. 



Very common on the cactus plain about Azua and also near Barahona, Santo Domingo ; 

 collected near Azua, March 1913, by Rose, Fitch, and Russell (No. 3837, type); also by 

 Paul Bartsch in Haiti, 1917; also on the northern coast of Venezuela, and on Margarita 

 Island, and apparently in Trinidad, as indicated by a colored drawing in the Kew her- 

 barium received in 1825 from David Lockhart. 



The plant grows in great abundance in Santo Domingo with other cacti, and cer- 

 tainly appears to be indigenous. Its nearest relative is 0. leptocaulis, from which it 

 differs in its greater size, thicker joints, and larger fruit. 



Figure 58 represents a joint of a plant collected by Rose, Fitch, and Russell at Azua, 

 Santo Domingo, in 1913; figure 59 is from a photograph of the type plant taken by Paul 

 G. Russell. 



