1012 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



by minute bracts ; areoles borne along the margin of the flat-branched forms, 

 along the ribs or scattered irregularly in the other forms, usually small, 

 bearing hairs, wool, bristles and flowers; flowers usually solitary, small; 

 perianth segments distinct, few, sometimes only 5, usually spreading, sometimes 

 reflexed ; filaments few or numerous, erect, slender, borne on the outer margin 

 of the disk in one or two rows; stigma lobes 3 or more, usually slender, 

 spreading ; ovary small, sometimes depressed or sunken in the branch ; fruit 

 globular or oblong, sometimes angled when immature, but finally turgid, juicy, 

 white or colored, usually naked. 



Numerous other species occur in tropical America, mostly in South America. 



Stems terete 1. R. cassutha. 



Stems flattened 2. R. purpusii. 



1. Rhipsalis cassutha Gaertn. Fruct. & Sem. 1: 137. 1788. 

 Eastern Mexico. West Indies and South America. 



Epiphytic or saxicolous, usually growing on trunk or branches of large 

 trees, hanging in large clusters, 1 to 4 meters long, the branches weak and 

 pendent, when young bearing 5 to 9 white bristles at the areoles, when old 

 naked, terete, sometimes producing aerial roots, often only 3 mm. in diameter, 

 light green, usually growing from the tips of other branches, generally in 

 pairs but sometimes in clusters of 6 or 8 ; flowers lateral, solitary, small 

 greenish in bud, sometimes subtended by a single bristle ; petals 2 mm. long, 

 cream-colored ; ovary exserted ; fruit naked, white, maturing a few days after 

 flowering, globose, 5 mm. in diameter. 



2. Rhipsalis purpusii Weingart. Monatsschr. Kakteenk. 28: 78. 1918. 

 Chiapas ; type from Cerro de Boqueron. 



Plant epiphytic ; stems 8 mm. in diameter, woody, terete, brown ; branches 

 weak, elongate, terete below, flattened above, thin, remotely crenate ; flowers 

 small, white, solitary. 



117. THYMELAEACEAE. Mezereum Family. 



1. DAPHNOPSIS Mart. & Zucc. Nov. Gen. & Sp. 1: 65. 1824. 



Reference: Meisner in DC. Prodr. 15: 520-524. 1856. • 



Trees or shrubs ; leaves alternate, entire, coriaceous, estipulate ; flowers 

 by abortion dioecious, umbellate or subracemose, axillary or terminal; peri- 

 anth of staminate flower with a slender tube and 4 spreading lobes ; stamens 

 8, 4 inserted on the perianth lobes and 4 in the throat, the anthers sessile; 

 perianth of pistillate hower smaller, turbinate or ui'ceolate; style short, the 

 stigma capitate; frui!; subglobose, 1-seeded, drupaceous, with thin pericarp. 



Leaves variously pubescent beneath. 



Leaves densely tomentose beneath with matted hairs 1. I>. purpusii. 



Leaves covered beneath with straight stiff hairs 2. D. mollis. 



Leaves glabrous beneath, except sometimes when very young. 



Leaves elliptic-lanceolate, broadest at or below the middle 3. D. lindenii. 



Leaves obovate to linear-oblanceolate, broadest above the middle. 



Peduncles elongate, much longer than the flowers 4. D. bonplandii. 



Peduncles short, usually shorter than the combined flower and pedicel. 

 Leaves linear-oblanceolate, 5 to 10 cm. long, 8 to 14 mm. wide. 



5. D. salicifolia. 



Leaves oblong-oblanceolate, 3.5 to 7 cm. long, 10 to 20 mm. wide. 



6. D. cestrifolia. 



