484 KOSACEAE (ROSE FAMILY) 



3. Styles filiform, lateral; peduncles axillary, solitary, \-flowered; achenes 

 glabrous; receptacle veryvillous; herbaceous perennials., with yellow petals. 



17. P. Anserina L. (SILVER WEED.) Spreading by slender many-jointed 

 runners, white-tomentose and silky-villous ; leaves all radical, pinnate ; leaflets 

 7-21, with smaller ones interposed, oblong, sharply serrate, silky-tomentose at 

 least beneath ; bractlets and stipules often incisely cleft ; peduncles elongated. 

 (Argentina Rydb. ) Brackish marshes, river-banks, etc., Arctic Am., s. to. 

 N. J., Great L. region, la., N. Dak., N. Mex., and Cal. June-Aug. (Eurasia.) ^ 

 P. Egedii Wormsk., at least as to forms in our range, appears to be a dwarf* 

 state common on exposed rocks. Var. grandis T. & G., is merely a luxuriant 

 state in rich meadows. 



Var. c6ncolor Ser. Leaflets silky -canescent above as well as beneath. 

 Common in the Rocky Mts., and in less pronounced form from u. N. Y. to n. Me. 

 and e. Que. 



18. P. pumila Poir. Stems very slender, soon prostrate and repent, appressed- 

 villous, flowering from the node above the first well-developed internode ; leaves 

 3-foliolate but apparently 5-foliolate by the parting of the lateral leaflets ; leaflets 

 cuneate-obovate, incisely dentate, obscurely appressed-villous above, sitfcy- 

 canescent beneath. Dry soil, common, coast of Me. to Md. Apr.-early June. 

 A loosely spreading-villous doubtfully distinct plant from Mo. and southeastw. 

 may well be P. CAROLINIA.XA Poir. 



19. P. canadensis L. Suberect (2-7 dm. high) or procumbent, at length 

 often rooting at the tip ; stem spreading-hirsute, flowering from the node above 

 the second well-developed internode , leaves divided as in the preceding ; leaflets 

 commonly more oblong, serrate rather than dentate, obscurely villous or entirely 

 glabrate above, canescent-silky to green and merely appressed-villous on the 

 veins beneath. Dry sandy soil, s. Me. to Vt., along the Great Lakes to Minn., 

 Kan., and southw. May-July. 



Var. simplex (Michx.) T. & G. Stem covered with shorter oppressed or sub- 

 oppressed hairs or glabrate; leaflets (apt to be oblanceolate) rather shortly 

 appressed-villous on the veins beneath. (P. simplex Michx.) Chiefly in dry 

 sandy soil, very common ; N. S., southw. and westw. 



20. P. REPTANS L. Stems almost filiform, sparingly pubescent or glabrate, 

 prostrate and usually repent ; leaves much as in P. pumila ; the leaflets green 

 on both faces, sparingly strigose-pubescent or glabrate, cuneate-oblanceolate, 

 crenate-dentate nearly or quite, to the base; stipules usually small and incon- 

 spicuous ; bractlets ovate-lanceolate, about equaling the calyx-lobes ; petals 

 broadly obcordate, half longer than the calyx-lobes. Grass-land and waste 

 places, local, Mass, to N. J. and O. June. (Adv. from Eu.) 



21. P. PROCUMBENS Sibth. Similar, strigose-pubescent; leaflets 3 (rarely 5), 

 cuneate-obovate, coarsely incised chiefly above the middle ; stipules conspicuous ; 

 bractlets linear-lanceolate. (P. nemoralis Nestler.) Grassy and waste places, 

 Cape Breton I., N. S. (Nat. from Eu.) 



16. FILIPENDULA [Tourn.] HilL 



Flowers perfect or polygamous. Calyx (4-)5-parted. Petals (4-) 5, short- 

 clawed. Stamens 20 or more, almost hypogynous, the disk obscure. Carpels 

 6-15, free, 2-ovuled, mostly 1-seeded, indehiscent, compressed, sometimes 

 twisted. Perennial herbs, with pinnate leaves and panicled cymose flowers. 

 Stipules kidney-shaped. (Name from filum, a thread, and pendulus, hanging, 

 in allusion, it is said, to the roots.) 



1. F. riibra (Hill) Robinson. (QUEEN OF THE PRAIKIE.) Glabrous, 6-25 

 dm. high ; leaves interruptedly pinnate, green and scarcely paler beneath ; 

 terminal leaflet large, 7-9-parted, the lobes lance-oblong, incised and toothed ; 

 lateral leaflets also cut ; petals deep peach-blossom-color. (Spiraea lobata 

 Gronov , Ulmaria rubra Hill.) Meadows and prairies, Pa. to Mich., la., Ky., 

 and Ga. also locally established uortheastw. June, July. 



