182 JOURNAL OF THE WASHINGTON ACADEMY OF SCIENCES VOL. 11, NO. 8 



was one of the plants called "Atlinan" by the Aztecs, who called it "Sister of 

 the Ololiuhqui" and invoked its spirit in treating certain diseases.^" 



Section IV. Brugmansia (Persoon). 



Flowers pendulous, very large; calyx not circumscissile near the base, either 

 falling off entirely or persisting as a husk-like envelope about the base of the 

 fruit; fruit unarmed, smooth, spheroid, oblong, fusiform, or linear and terete. 



Type of the section. Datura Candida (Persoon). 



KEY to the species 



Calyx spathe-like, terminating in a point. 

 Flower white. 



Corolla more than 20 cm. long; margin of limb between the teeth entire 



or rounded. 11. D. Candida. 



Corolla not exceeding 17 cm. in length; margin of limb between the teeth 

 cordate or emarginate. 

 Calyx tapering into a horn-like point. 12. D. cornigera. 



Calyx without a horn-like apex. 13. D. arborca. 



Flower colored. 



Corolla large, more than 25 cm. long. 



Peduncle, petioles and young branches glabrous; corolla at length 



turning red. 14. D. versicolor. 



Peduncle, calyx, nerves of the corolla, and margins of corolla teeth 

 clothed with soft hairs; corolla pink. 15. D. mollis. 



Corolla small, not exceeding 15 cm. in length, red. IG. D. rubella. 

 Calyx toothed at the apex. 

 Flower white. 



Anthers coherent; corolla teeth short, about 1 to 2 cm. long. 



17. D. suaveolens. 

 Anthers distinct; corolla teeth 2 to 5 cm. long. 



Fruit ovoid. IS. D.affinis. 



Fruit long and slender. 



Leaves lanceolate to ovate-lanceolate, entire. 19. D. dolichocarpa. 

 Leaves linear-oblong, sinuate-repand. 20. D. longifolia. 



Flower colored. 



Calyx deciduous, more than half the length of the corolla. 



Apex 5-toothed; fruit narrowly ovoid, beaked. 21. D. aurea. 

 Apex 2-toothed ; fruit elongate-ovoid, not beaked. 22. D. pittieri. 

 Calyx persistent, less than half the length of the corolla. 



Uppermost leaves entire or repand, puberulent. 2."). D. sanguinea. 

 Uppermost leaves angular-toothed, densely tomentose. 



24. D. rosei. 



11. Datura Candida (Pers.) Saflford. 



Datura arborea Ruiz & Pavon, Fl. Peruv. 2: 15. pi. 12". 1799. Not D. 



arbor ea L. 17-53. 

 Brtigmansia Candida Pers. Syn. PI. 1: 210. 1805. 



Type Locality: "Habitat in Peruviae hortis, versuris et septis, passim ad 

 Cercado, Chancay, et Huanuci Provincias." 



Range : Known only in cultivation ; now widely spread in tropical and sub- 

 tropical countries. 



"> Jacinto de la Serna, in Documentos Ined. para la Hist, de Espana 104: 159-160. 



