ROSACEAE (ROSE FAMILY) 253 



1. Chamaerhodos erecta (L.) Bunge, in Ledeb. Fl. Alt. 1: 430. 1829. 

 Stem slender, paniculately branched above, 1-3 dm. high: radical leaves 

 rosulate, ternately or biternately many cleft: sepals lanceolate, nearly equal- 

 ing the short white obovate-cuneate petals. From Canada to Wyoming and 

 northwestward. 



20. DRYMOCALLIS Fourr. 



Perennial, usually glandular-viscid herbs, with pinnate leaves and irreg- 

 ularly cymose flowers. Sepals 5, with 5 alternating bractlets. Petals 5, 

 white or yellow. Stamens 20-30, in five fascicles on the thickened margin of 

 a disk around the receptacle. Receptacle hemispheric, bearing the numerous 

 pistils. Style inserted near the base of the ovary, thickened and glandular a 

 little below the middle and tapering to both ends; the stigma minute. Po- 

 tentilla in part. 



Petals white, often turning yellowish in drying. 

 Petals and sepals subequal. 



Inflorescence crowded; leaves densely pubescent . . . 1. D. arguta. 



Inflorescence open; leaves glabrate 2. D. convallaria. 



Petals distinctly longer than the sepals . . . . . 3. D. pseudorupestris. 



Petals evidently yellow. 



Petals and sepals subequal . . . ... . . 4. D. glandulosa. 



Petals distinctly longer than the sepals. 



Inflorescence crowded ; the plant glandular-hirsute .' . 5. D. fissa. 



Inflorescence open; the plant viscid-glandular . . . 6. D. glutinosa. 



1. Drymocallis arguta (Pursh) Rydb. Mem. Dept. Bot. Columbia Univ. 

 2: 192. 1898. Erect, stout, glandular and villous pubescent, 3-7 dm. high: 

 leaflets of basal leaves 7-11, ovate or rhomboid-ovate; the terminal one 

 cuneate, the others rounded at base and somewhat oblique; all incisely ser- 

 rate: stem leaves with few leaflets and often subsessile: flowers white, densely 

 cymose: petals obovate, scarcely longer than the acute sepals. Potentilla 

 arguta Pursh. From Colorado eastward to the New England States. 



2. Drymocallis convallaria Rydb. 1. c. 193. Sparsely long-villous, viscid- 

 glandular above, 4-8 cm. high, somewhat branched above: basal leaves with 

 9-11 glabrate or somewhat pubescent obovate obtuse incisely serrate leaflets, 

 on long petioles, villous at base; the stem leaves smaller, with subacute leaf- 

 lets: cyme branched; the flowers on short pedicels: calyx villous, glandular- 

 viscid: petals obovate, white, drying yellowish, scarcely longer than the sepals 

 which are much longer than the bractlets. Potentilla glandulosa Lindl. in 

 part. From Wyoming to Washington. 



3. Drymocallis pseudorupestris Rydb. 1. c. 194. Sparingly glandular- 

 villous, the slender striate stems with ascending branchlets above, 2-4 dm. 

 high: basal leaves short-petioled, with 7-9 sparsely pubescent or glabrate 

 leaflets; the terminal one obovate or cuneate-flabellif orm ; the lateral ones 

 obliquely elliptic or suborbicular; all incisely serrate, with ovate mucronu- 

 late teeth; stem leaves few, with 3-5 leaflets: inflorescence open, the flowers 

 on slender pedicels : calyx viscid-villous, scarcely enlarged in fruit : petals ob- 

 ovate, white, drying yellowish, exceeding the sepals by a third: bractlets 

 much smaller than the sepals. Through northern Wyoming to Washington. 



4. Drymocallis glandulosa (Lindl.) Rydb. 1. c. 198. Viscid and glandular- 

 hairy, especially upward, the stem simple below, irregularly branched above: 

 basal leaves petioled, pinnate or interruptedly pinnate; leaflets 7-9, sparingly 

 hairy or glabrate above, obovate, obtuse, 1-3 cm. long, with broad teeth: cyme 

 open, many-flowered : calyx glandular-hirsute, bractlets almost linear, much 

 shorter than the sepals: petals yellow, obovate, not longer than the sepals, 

 which in fruit are 8-10 mm. long. Potentilla glandulosa Lindl. in part. Da- 

 kota to New Mexico, west to California. 



5. Drymocallis fissa Nutt. Rydb. 1. c. 197. Glandular-hirsute throughout, 

 rather freely branched, 2-3 dm. high: basal leaves short-petioled, with about 

 9 suborbicular, subrhombic, and incisely doubly serrate leaflets; stem leaves 

 similar but reduced: flowers yellow, large, 2 cm. in diameter, in a narrow 



