Chrysosplenitjm. SAXIFRAGACEyE. 259 



roundish-ovate, obscurely crenate-lobed ; flowers dichotomal, distant, nearly sessile. — 

 Schweinitz, mss.; Hook. fl. Bor.-Am. 1. p. 242 ; Darlingt. fi. Cest. p. 270 ; Torr. ^ Gr. 

 fl. N. Am. 1. p. 589. C. opposilifolium, Michx. fl. 1. p. 269 ; Pursh, fl. 1. p. 299 ; Ell. 

 sk. 1. p. 511 ; Torr.fl. 1. p. 445 ; Bigel. fl. Bost. p. 154, not of Linn. 



Root perennial. Stems spreading and often forming a dense mat ; the flowering branches 

 sometimes assurgent. Leaves about half an inch in diameter, often broader than long, abruptly 

 narrowed at the base into a distinct petiole. Flowers scarcely more than 2 lines in diameter, 

 on very short pedicels in the uppermost forks of the stem, and terminal. Calyx mostly 4- 

 cleft, green and slightly purple inside. Stamens mostly 8, very short : filaments inserted into 

 the indentations of the purplish disk : anthers at first orange-red, at length turning brown. 

 Styles divaricate. Capsule dehiscent between the two short beaks. Seeds 10 - 12, hispid, 

 brownish. 



About springs and in brooks, usually in shady places ; common. April - May. This 

 species was for a long time regarded as the C. oppositifolium of Europe. The latter is, 

 however, a much stouter plant, with larger yellow flowers. The late Mr. Schweinitz first 

 pointed out the difference between the two species. 



Group 17. Ovary compound, 2- (rarely 3 - b-) celled, with a single ovule suspended 

 from the summit of each cell. Stamens as many as the petals (or numerous in 

 Fothergilla) and lobes of the adherent calyx. 



Order XL VII. HAMAMELACEiE. R. Br. The Witch-hazel Tribe. 



Calyx 4 - 5-cleft, or with 5-7 obscure teeth ; the tube more or less adherent. 

 Petals 4-5, long and narrow, rarely wanting. Stamens either twice the 

 number of the petals, the alternate ones sterile and scale-like ; or (in Fother- 

 gilla) numerous and all fertile : cells of the anthers opening by valves. 

 Ovary composed of 2 united carpels, the summit free from the calyx : styles 

 2, distinct. Capsules cartilaginous or bony, 2-beaked, 2-celled, dehiscent at 

 the summit. Seeds bony. Embryo straight, in the axis of fleshy albumen. — 

 Shrubs or small trees, with alternate simple feather- veined leaves and deciduous 

 stipules. Flowers often polygamous, in sessile fascicles or heads. 



33* 



