152 



THE CACTACEAE. 



Stewart himself, for he calls attention to procumbent and arborescent forms of 0. gala- 

 pageia, while the greatest range of spine characters is shown between the young plants and 

 old ones and between the trunk and the joints. The specimen which Mr. Stewart has 

 made the type of his Opuntia insularis is quite different from all the others, and yet one 

 can easily believe that intergrades could be found ; his species is described without flowers 

 or fruit. Mr. Stewart states that this Opuntia forms the principal article of food for the 

 Galapagos land tortoise. Its trunk becomes thicker than that of any other known species 

 of the genus. 



Illustrations: Gard. Chron. III. 24: f. 75 ; Mag. Zool. and Bot. i : pi. 14, f. 2 ; Proc. Calif. 

 Acad. IV. I : pi. 7, f. 2; pi. 8; pi. 9, f. 2; pi. 10 to 12. Gard. Chron. Ser. III. 27: f. 56; Proc. 

 Calif. Acad. IV. i: pi. 7, f. i; pi. 13, f. 2; pi. 16 to 18, all as Opuntia myriacantha. Proc. 

 Calif. Acad. IV. i: pi. 13, f. i; pi. 14, the last two as Opuntia helleri. Proc. Calif. Acad. 

 IV. I : pi. 9, f. I ; pi. 15, the last two as Opuntia insularis. 



Figure 189 represents a joint of the plant collected by Robert E. Snodgrass and 

 Edmund Heller on Wenman Island, Galapagos, on the Hopkins-Stanford Expedition (type 

 of Opuntia helleri Schumann), drawn from the herbarium specimen in the Gray Herbarium; 

 figure 190 is of a flower of the same plant; figure 191 is from a photograph of an herbarium 

 specimen collected by Alban Stewart. 



155. Opuntia delaetiana Weber in Vaupel, Bliihende Kakteen 3: pi. 148. 1913. 



Opuntia elata delaetiana Weber in Gosselin, Bull. Mus. Hist, Nat. Paris lo: 392. 1904. 

 Joints oblong, 25 cm. long, 8 cm. broad, bright green, at first thin and spineless, the margin 

 strongly undulate ; areoles large, bearing 3 to 5 straight, rose-colored or yellowish brown spines up to 

 4 cm. long; leaves subulate, about 4 mm. long; glochids wanting in young areoles, later appearing 

 numerous and brown; flower-buds rounded at the apex; outer sepals orbicular, obtuse, red; flower 

 rotate, 5 to 7 cm. broad, orange-colored; stigma-lobes white; fruit oblong or pyriform, red, 5 to 7 cm. 

 long, 3 to 5 cm. in thickness. 



Type locality: Paraguay. 



Distribution: Paraguay and northeastern Ar- 

 gentina. 



The plant was collected by Dr. Thomas 

 Morong at Asuncion, Paraguay, in 1888, and re- 

 ferred in his list of plants collected in Paraguay 

 (Annal. N. Y. Acad. Sci. 7: 121. 1892) to 0. nigri- 

 cans Haworth; Dr. Shafer found it in 19 17 in waste 

 places and in hedge-rows about Concordia and Po- 

 sados, Argentina. This species may more prop- 

 erly belong in our series Elatae than in Elatiores. 



Illustration: Bliihende Kakteen 3: pi. 148. 



Figure 192 is copied from the illustration 

 above cited. 



156. Opuntia bergeriana Weber in Berger, Gard. Chron. 

 111.35:34- 1904- 

 Growing singly or in dense thickets, qften i to 3.5 



meters high and having a trunk 3 to 4 dm. in diameter, 

 with a large, spreading top, or clambering over walls 

 and rocks; joints narrowly oblong, sometimes 2.5 cm. 

 long, when young often quite narrow, bright green, but 

 becoming dull and somewhat glaucous; areoles rather distant, on old joints 2 to 4 cm. apart, filled 

 with short gray wool; spines 2 or 3, rarely 5, unequal, the longest one 3 to 4 cm. long and somewhat 

 flattened, more or less brownish at base, sometimes yellowish, porrect, or somewhat turned down- 

 ward; leaves 2 to 3 mm. long, fugacious; glochids yellow but sometimes turning brown, rather promi- 

 nent, formmg a half circle in the upper part of the areole; areoles circular, when young filled with 

 light brown wool m the center and white in the outer region; flowers numerous, showy, deep red; 



Fig. 192. — Opuntia delaetiana. 



