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



Hypanthium and Calyx. The hypanthium is more or less campanulate. The 

 ribs, scarcely visible externally, are 2n in number and run to the torus. The term 

 "torus" is here used in the sense of Gleason (1939) as the ring of vascular tis- 

 sue at the apex of the hypanthium upon which the petals and stamens are inserted. 

 The sepals extend from the torus and are "united" above it to varying degrees; in 

 the specific descriptions, the sepal lengths are measured from the torus, the widths 

 from sinus to sinus; the "calyx lobes" are the free portions of the sepals. Both 

 sepals and hypanthium are pubescent to varying degrees externally; the hypan- 

 thium is glabrous within, the sepals usually so except for a sparse sprinkling of 

 inconspicuous minute appressed hairs which are similar to the glands of the lower 

 leaf surface but more elongate. Occasionally the sepals are, as specifically noted, 

 pubescent within apically. The marginal and external surface hairs of the sepals 

 are usually developed to the same degree as the hypanthial pubescence. The se- 

 pals are imbricate in bud but usually not noticeably so at anthesis; in some spe- 

 cies, however, imbrication at anthesis has been used as a key character. In fruit 

 the sepal lobes become lengthened, twisted, and incurved; for species, such as 

 B. strigosum y in which the sepals are imbricate at anthesis, this later growth 

 markedly changes the sepal shape and obliterates the imbrication. 



Corolla. As in all Melastomaceae, the petals of Brachyotum are right-contort. 

 They never spread, remaining connivent and imbricate in a polypetalous tube which 

 falls off as a unit after anthesis. Such a tube is not unique for the Melastomaceae, 

 being found also in Axinaea, Charianthus , Purpurella (Tibouchina) itatiaiae 

 Wawra, and P. hospita (Schrank & Mart.) Krasser. The petals are rather firm in 

 texture, obovate, and asymmetrical to varying degrees. The apices range from 

 acute to obtuse to truncate or obliquely truncate. In the acute, obtuse, and sym- 

 metrically truncate petals, the midvein traverses the length of the petal; in ob- 

 liquely truncate petals, the midvein terminates along the oblique end of the petal 

 rather than at the dimensional apex. Generally the petals are glabrous except for 

 the marginal cilia; in a few instances, they are sparsely to moderately pubescent 

 without. Cilia are developed in all species; in those described as with gland- 

 tipped cilia, the larger terminal few cilia are apparently eglandular; in those de- 

 scribed as eglandular, rarely a few of the basal cilia have inconspicuous heads; 

 in some species, even the well-developed glandular tips are caducous before an- 

 thesis. The cilia extend to within a few millimeters of the base of the petal. Petal 

 color is apparently quite specific; it ranges from deep purple or blue (almost 

 black) to carmine or white with red margins to greenish-white or yellowish. 



Androecium. Anthers and the upper portions of the filaments are inflexed in 

 bud, becoming erect at anthesis. "Anthesis" as here used is the time at which 

 this ejection occurs, and the dimensions and shape of all inflorescence and flower 

 organs have been based on this stage in development. The glabrous filaments are 

 flattened dorso-ventrally, the cross section being a flattened triangle with the 

 apex facing inward, lateral flanges being slightly developed at the base of the fil- 

 ament. There are one or two irregularly placed "nicks" on the inside of the fila- 

 ment where it is bent before anthesis. During anthesis, the filament elongates 

 markedly. 



The glabrous anthers are usually slightly arcuate and lanceolate, tapering from 

 the bases of the thecae to the apical pore; in B. lycopodioides and its relatives, 

 however, the anthers are short and oblyrate, with more or less flaring apices due 

 to the large pores which are half or more as wide as the bases of the anthers. The 

 anthers are two-celled and dehisce by an apical pore which apparently is open 

 long before anthesis; each theca is rounded-elliptic in cross section. Frequently 



