94 ROSACEA. 



White Hills, N. H. N. lo Labrador. July. Il.—Flower vvliite, on a temu- 

 nal peduncle. Scarcely distinct from D. octopetala Linn. 



Entire-leaved Dryas. 



4. GEUM. Linn. — Avens. 



(From the Greek yevo), to yield an agreeable flavor ; the root of one species 

 being aromatic.) 



Calyx concave; limb 5-cleft, with 5 small external bracts 

 alternating with the segments. Petals 5. Stamens numerous, 

 inserted into the disk that lines the base of the calyx. Carpels 

 in a head, awned by the persistent styles. 



1. G. stridum Ait.: hairy; radical and lower leaves interruptedly pin- 

 nate ; upper cauline ones 3— 5-foUate; the leafets rhombic-ovate, acute, 

 sharply toothed and incised ; stipules large, incised ; petals roundish, longer 

 than the calyx. C. Canadense Murr. 



Swamps. Can. N. Y. and New Eng. Aug. nX.—Stem 2—4 feet high, 

 pimple. Radical and lower leaves on long petioles, the upper nearly sessile. 

 Flowers large, yellow, in a loose dichotomous panicle. Yellow Avens. 



2. G. Virginianum Linn. : pubescent ; radical leaves pseudo-pinnate or 

 ternate ; upper simple, lanceolate, incisely serrate ; stipules subovate, entire 

 or incised ; petals cuneate-obovate, shorter than the calyx. G. aUntm 

 Willd. 



Woods. Can. to Geor. W. to Miss. June, July. %..—Stem 2—3 feet high, 

 smooth, or pubescent. Radical leaves on long petioles. Flowers white or pale 

 yellow, on peduncles 1 — 3 inches long terminating the branches, at first some- 

 what nodding, at length erect. Virginian Avens. 



3. G. macrophylhim Wllld. : hispid ; radical leaves lyrately and inter- 

 ruptedly pinnate ; cauline with 2 — 4 minute lateral leafets, the terminal one 

 large roundish and 3-parted; stipules nearly entire; petals obovate, a little 

 longer than the calyx. 



White Mountains. N. H. N. to Arct. Amer. W. to the Pacific. June, 

 July. %. — Stem 1 — ^2 feet high, very hispid. Leaves sometimes nearly smooth. 

 Flowers yellow, intermediate in size between G. stridum and Virginianum. 



Long-leaved Avens. 



4. G. rivale Linn. : pubescent ; stem simple, 1—4 flowered ; radical 

 leaves interruptedly pinnate ; cauline ternate or3-lobed; petals broad ob- 

 cordate-spatulate, emarginate, about as long as the calyx ; carpels in a 

 stipedhead, very hairy; upper joint of the style plumose. 



Moist places. Can. to Penn. W. to tlie Rocky Mountains. May, June. %. — 

 Stem 18 inches or 2 feet high, nearly simple, somewhat pilose. Radical leaves 

 on very long petioles. Flowers large, purple, nodding. Water Avens. 



5. G. trijlorum Pursh. : stem nearly naked, softly pubescent, about 

 3-flowered at the summit ; radical leaves interruptedly pinnate, the petioles 

 hairy ; leafets cuneiform-oblong, deeply incised and toothed ; bracts longer 

 than the segments of the calyx ; styles very long and filiform in firuit, 

 plumose. Sieversia trijlora R. Brown. 



On rocks. Watertown, Jefferson county, N. Y. ; very rare. Dr. Crawe. 

 ^Vhite Mountains, N. H. W. to the Rocky Mountains. N. to Labrador. May, 

 June. %. — Stem 4 — 6 inches, in fruit 12 — 15 inches high, with two opposite 



