HEUOCEREUS. 129 



Cercus sctigcr Haworth, Phil. Mag. 7: no. 1830, although said to have come originally 

 from Brazil, probably belongs here. Cercus aurantiacum sitpcrbus Haage (Labouret, 

 Monogr. Cact. 428. 1853), a hybrid of this species, is only mentioned. 



Cereus josselinacus D. Gaillard (Rev. Hort. 5: 56. 1841) is probably only a form. 



Cercus scrratns Weingart (Monatsschr. Kakteenk. 22: 185. 1912) is of this relationship. 

 Rother believed it was of hybrid origin and Weingart at first agreed, but afterwards con- 

 sidered it distinct. 



Cercus mexicciiins Lcmaire (Forster, Handb. Cact. 430. 1846) is a hybrid of which 

 Helioccrcus speciosus is one parent. 



Illustrations: Bliihende Kakteen i:pl. 17; Schumann, Gesamtb. Kakteen f. 36, as 

 Cereus speciosus; Herb. Gener. Amat. 5: pi. 351 ; Curtis's Bot. Mag. 4Q:pl. 2306; Loddiges, 

 Bot. Cab. 10: pi. 924; Mem. Mus. Hist. Nat. Paris 3: pi. 9; Edward's Bot. Reg. 6: pi. 4; 

 28: pi. 49; Loudon, Encycl. PI. 410. f. 6857, as Cactus spcciosissimus; Schelle, Handb. 

 Kakteenk. f. 35, as Cercus spcciosissimus. 



Plate xvii, figure 2, shows a flowering joint of a plant in the collection of the New York 

 Botanical Garden. 



4. Heliocereus cinnabarinus (Eichlam). 



Cercns cinnabar inns Eichlam in Weingart, Monatsschr. Kakteenk. 20: 161. 1910. 



Stems erect or in time creeping and more or less rooting, very slender, i to 1.5 cm. in diameter; 

 ribs few, sometimes only 3 or 4; areoles 2 to 3 cm. apart; spines about 10, bristle-like, 6 to 8 mm. 

 long; flowers about 15 cm. long, the tube bent just above the ovary, more or less funnelform; outer 

 perianth-segments narrow, acute, green; inner perianth-segments oblong to spatulate, sometimes 

 2.5 cm. broad, abruptly acuminate, somewhat erose toward the apex; style rose-colored; stigma- 

 lobes 7, white. 



Type locality: Vulcan Agua, Guatemala. 



Distribution : Guatemala. 



We know the plant from specimens collected by E. W. Nelson on the volcano of Santa 

 Maria, altitude 2,600 to 3,800 meters, January 24, 1896 (No. 3719). 



It is like Heliocereus elegantissimus, but with slenderer stems, lower ribs, weaker 

 spines, and abruptly acuminate inner perianth-segments. 



This must be a very beautiful species and, growing at such high altitudes in Guatemala, 

 suggests the possibility of its cultivation in the open in certain parts of the United States. 



5. Heliocereus amecamensis* (Heese) Britton and Rose, Contr. U. S. Nat. Herb. 12: 433. 1909. 



Cereus amecamensis Heesef in Rother, Prakt. Ratgeb. n: 442. 1896. 

 Cereus amecaensis Heese, Gartenwelt 1:317. 1897. 



Plant pale green when young, similar to //. speciosus in habit and spines; ribs 3 to 5; flower n 

 cm. long, 8 to 12.5 cm. in diameter; flower-tube 3.5 cm. long, i cm. in diameter, green, with green 

 scales and whitish bristles; outer perianth-segments yellowish green, grading into oblanceolate white 

 inner segments, 7 cm. long, 2 cm. wide; stamens white except the pale-green bases, attached all 

 over the tube; anthers creamy white; style white, slightly exserted beyond the stamens, strongly 

 curved down in the tube; stigma-lobes u, linear, light creamy white; ovary cylindric, 6 mm. long. 



Type locality: Amecameca, Mexico. 



Distribution: Central Mexico. 



This species has been introduced into Europe by Dr. C. A. Purpus, where it is now 

 much cultivated. 



Illustrations: Curtis's Bot. Mag. 135: pi. 8277; Rother, Prakt. Ratgeb. 11:442; Gar- 

 den 76: 306, all as Cereus amecamensis: Bluhende Kakteen 3: pi. 157; Gard. Mag. 55: 427; 



Gartenwelt i: 316, 317. f. i to 3, as Cercus amecaensis. 



^ 



* Confusion of the type locality, Amecameca, with another Mexican town, Ameca, doubtless accounts for the 

 two spellings of the name of this plant. 



t Rother here spells this name Hesse, doubtless erroneously. 



