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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN [Vol. 8, No. 4 



Of the 141 examinable flowers in the various collections ascribed to this spe- 

 cies, all except 20 were 5-merous. All except 6 of the 39 examinable flowers of 

 Lechler 2061 were 5*merous, although B. trianaei was described as 4-merous. 



The degree of distinctness of this complex from B. lutescens is dubious; some 

 specimens vary toward B. lutescens and some toward B. rosmarinifolium. The in- 

 terplay of appressed and patent stem pubescence and glandular and non-glandular 

 stem, lower leaf surface, and hypanthial trichomes certainly permits no specific 

 distinctions between the species synonymized under B. rostratum. "Typical" B. 

 trianaei (B. callosum) has spreading to appressed stem pubescence, loosely ap- 

 pressed to spreading lower leaf surface hairs, and appressed to loosely appressed 

 hypanthial hairs, all such hairs being eglandular except for a very few of the 

 sinusal ones; such collections are Isern 583, Lechler 2061, Macbride & Feather- 

 stone 2181, Metcalf 30548, Raimondi 9439, and Stork & Horton 10429, Dombey 

 s.n. and Ferreyra 7504 have very long, dense, spreading to loosely appressed 

 stem hairs, with gland-tipped ones more or less abundantly intermingled with 

 the non-glandular on the stems, lower leaf surfaces, and hypanthia; the leaves 

 are ovate to ovate-elliptic. Asplund 11900, Ochoa 206, Pennell 13847a, Soukup 

 387, and Vargas 2057 have mostly lanceolate to oblong leaves which have non- 

 glandular hairs beneath (except Asplund 11900) and many of the hypanthial 

 hairs gland-tipped; the style of Vargas 2057 is very sparsely beset with stout 

 spreading hairs on the basal %, In B. microphyllum, the young leaves on the 

 flowering branches are elliptic to oblong, but the leaves on vegetative shoots 

 are ovate; the hairs on the upper leaf surfaces have exceptionally well-developed 

 calloused bases; only a very few stem hairs, the petal cilia, and the young 

 ovary hairs are gland-tipped; such collections are Bonpland s.n. and Sandeman 

 4118. Except for the greater pubescence density and longer free apices on the 

 upper leaf surface hairs, these two specimens resemble the "trianaei" element, 

 having similar scanty development of gland-tipped hairs. 



Jameson s.n. (K), from Pillzhum in Ecuador, resembles B. rostratum in its ter- 

 nate 5~merous flowers with glandular hypanthia, but the leaves are much less pu- 

 bescent beneath than usual and the connective is free of the anther base 0.2 mm.; 

 further collections are needed to establish the status of this specimen. 



43. Brachyotum lutescens (R. & P.) Triana, Trans. Linn. Soc. 28: 48. 1871. 



Rhexia lutescens R. & P. Fl. Peruv. & Chil. 3: 84. 1802. 

 Arthrostemma lutescens (R. & P.) DC. Prodr. 3: 136. 1828. 

 Alifana lutescens (R. & P.) Raf. Syl. Tell. 101. 1838. 



Chaetogastra lutescens (R. & P.) Naudin, Ann. Sci. Nat. III. 14: 134, quoad syn. 1850. 



Trichomes minutely but moderately roughened, those on the branchlets, lower 

 leaf surfaces, hypanthia, and sepals in part gland-tipped at least when young, on 

 upper leaf surface often gland-tipped. Branchlets obscurely quadrangular, very 

 densely hirsute with the hairs to 2-3 mm. long. Petiole 2-5 nim. Blade (8-)10-18 

 x (4-)6-9 mm., ovate to elliptic-ovate with the apex blunt-acute and the base ob- 

 tuse to subtruncate, the 3 primaries impressed above and elevated below, the 10- 

 15 pairs of secondaries obscurely impressed above and thinly elevated below but 

 hidden by the pubescence; above moderately loose-strigose, the hairs 3~6/mm. 2 

 on very low bullae with their basal %-% adherent and slightly expanded and the 

 apical free portion to 1.5 mm. long; below moderately to densely hirsute, the hairs 

 9-12/mm. 2 and to 2 mm. long,- the glands solitary and dense (40-60/mm. 2 ). Flow- 

 ers predominantly 4-merous, the inflorescences and flowers otherwise as in B. 

 rostratum. 



Type Collection and Locality: Ruiz & Pavbn s.n. (SYNTYPES presumably at 

 MA; isosyntypes BM, BR, F, G-BOIS, G-DEL, P); Peru, Dept. Huanuco, "in monti- 

 bus Chaclla ad Pinapata et in Muna ad Tambo." 



