Il6 THE CACTACEAE. 



desert of Azua, Santo Domingo, this is the dominant cactus, forming dense, impenetrable 

 thickets on the low coastal plain. In the wild state the Azua plant has the joints often 

 bronzed or purple. On Tortola and St. Thomas it occurs with 0. dillenii and 0. re pens, 

 and is there called bull suckers. 



Figure 143 is from a photograph taken by Paul G. Russell in 19 13 near Azua, Santo 

 Domingo; figure 144 represents joints of the type plant. 



103(2. Opuntia caracasana Salm-Dyck. (See Appendix, p. 219.) 



104. Opuntia wentiana sp. nov. 



Opuntia tunoides Britton and Shafer in Boldingh, Fl. Ned. W. Ind. Eiland 300. 1913. Not 0. tunoidea 

 Gibbes. 



Plant erect, much branched, i to 2 meters high' joints obovate to elliptic, rather thin, up to 

 25 cm. long, usually rounded at apex, pale green, slightly glaucous; terminal joints somewhat fragile; 

 leaves small and subulate ; spines on young joints usually 3, afterwards 4 or 5, when young pale yellow 

 but soon white; flowers small, 6 to 7 cm. long including the ovary; petals pale yellow, 3 cm. long, 

 obovate, acute; style cream-colored; fruit small, red. 



Type locality: Curagao. 



Distribution: Venezuela, and the neighboring islands, Margarita, Bonaire, Curasao, 

 and Aruba. 



Dr. Rose found this plant repeatedly in Venezuela and writes of it as follows : Very 

 common not only on the savannas along the coast but also on the neighboring hills along 

 with Lemaireocereus, Cephalocereus, and other cactus genera; its more or less fragile joints, 

 yellowish spines, bushy stature, and structure of flowers ally it with the Tunae. 



This species has been confused with the Jamaican Opuntia tuna (Linnaeus) Miller, 

 which it resembles. Named in honor of Professor F. A. F. C. Went, distinguished 

 Dutch botanist. 



104a. Opuntia aequatorialis sp. nov. (See Appendix, p. 219.) 



105. Opuntia decumbens Salm-Dyck, Hort. Dyck. 361. 1834. 



Opuntia pubenila Pfeiffer, Eniim. Cact. 156. 1837. 



Stems low, often creeping or trailing, rarely over 4 dm. high; joints i to 2 dm. long, oval to 

 oblong, covered with a short, soft pubescence; areole usually small, surrounded by a purple blotch, 

 bearing yellow glochids and wool, the wool cobweb-like on very 3'oung joints; spines often wanting, 

 usually solitary but sometimes numerous, slender or rather stout, 4 cm. long and yellow; flowers 

 numerous, small, including the ovary about 4 cm. long; petals dark yellow; fruit deep purple, very 

 juicy; seeds about 4 nun. broad. 



Type locality: In Mexico. 



Distribution: Guatemala and Mexico as far north as Mazatlan and Tamaulipas. 



Opuntia repens Kanvinsky (Salm-Dyck, Hort. Dyck. 361. 1834) and 0. irrorata Mar- 

 tins are usually given as synonyms of this species, but as they were printed without 

 descriptions, they should hardly be referred to sjmonymy. 



The species has long been in cultivation, a colored illustration having been published 

 in Curtis's Botanical Magazine in 1841. It grows luxuriously in greenhouses, flowering 

 profusely in the spring. 



We have referred here Opuntia pubenila Pfeiffer, which seems to be different from the 

 plant now grown in collections under that name. Pfeiffer's original description, based upon 

 sterile plants alone, may be paraphrased as follows: Joints thick, obovate, 7.5 to 12.5 cm. 

 long by 5 to 7.5 cm. broad, puberulent, green; areoles somewhat remote, each surrounded by 

 a red spot, bearing in the upper part a bunch of short glochids and below 2 to 4 slender, 

 white, divergent spines, the longer ones 8 mm. long; leaves 4 mm. long, acute, red at apex. 



Labouret's description of 1853, of O. pubenila Pfeiffer, is very similar to Pfeiffer's, 

 except that he states that the spines are 9 cm. long. Both these descriptions answer very 



