566 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1920. 



somewhat smaller than the white-flowered Datura arborea L. and 

 having a very different appearance from that species, with a more 

 open habit, narrower leaves, and scarlet-and-orange flowers. At 

 Ollantaytambo it is locally known as Puca Campancho, puca being 

 the Quichua word for " red." Here it flowers abundantly, begin- 

 ning in May. About the middle of July only a single small fruit of 

 this species could be found in this locality, while trees of Datura 

 arborea were bearing an abundance of fruit. Higher up, however, 

 in the pass of Panticalla above Pinasfiiocj, at an altitude of 12,000 

 feet, where there was frost every night, trees were found fruiting 

 abundantly, showing it to be a hardy species, likely to grow in such 

 localities as the California coast region. On plate 12 are shown 

 specimens of flowers of this species collected by Mr. Cook, with 

 leaves and peduncle pubescent but not densely woolly as in Datura 

 rosei, and with the blades of the leaves entire instead of coarsely 

 toothed or notched. On plate 13 are two fruits of the same species, 

 the smaller collected by Mr. Cook at Ollantaytambo at an altitude of 

 9,500 feet, the larger at Pifianeniocj at an altitude of 12,000 feet. 



It is not strange that the tree daturas above described, with their 

 pendulous indehiscent fruit so very different in form from the erect 

 four-valved capsules of Datura stramonium, should have been re- 

 garded as a distinct genus (Brugmansia) by botanists who were unfa- 

 miliar with the other groups. This proposed genus " differs from 

 Datura in its treelike stem, its persistent longitudinally cleft calyx, 

 at length quite deciduous, its two-celled ovary and unarmed inde- 

 hiscent fruit." 36 As a matter of fact, in most of the species, including 

 Datura arborea (pi. 9), D. suaveolens (fig. 12), and D. pittieri (pi. 

 10) the calyx is not persistent; in D. suaveolens (pi. 11) it is five- 

 toothed at the apex and not split more than in D. meteloide® (pi. 4) ; 

 while in Datura sanguinea (pi. 13) it persists until the fruit is quite 

 ripe and is never deciduous. As for the ovary, it is really two-celled 

 in all species of Datura. The fruit of Datura ceratocaula (fig. 10) 

 is both unarmed and indehiscent, and none of the fruits of the section 

 Dutra (pis. 1, 2, 3) are really dehiscent, but break up irregularly 

 when quite mature. 



It therefore follows that the tree daturas of South America can 

 not be separated as a distinct genus on account of their split or decid- 

 uous calyx, their two-celled ovary, or their spineless indehiscent fruit. 

 As for the essential parts of the flowers and the forms of the corolla 

 they do not differ from those of other sections of Datura, with which 

 they are connected by the marsh-loving torna-loca (Datura cerato- 

 caula) of Mexico. 



^Lagerheim, G., in Engler's Jahrb., vol. 20, p. 662, 1895. 



