EOSACKiE. (kOSE FAMILY.) 119 



* Achenia glabrous ! style thickened above : receptacle conical in fruit. 



7. P. argfllta, Pnrsh. Stem erect and stout (2° -4° high), brownish 

 haiiy, clammy above ; leaves pinnace, of 3 - 9 oval or ovate cut-serrate leaflets, 

 downy underneath ; flowers cymose-clustered ; petals yellowish or whitish ; disk 

 thick and glandular. — Rocky hills ; common northward. July. 



* * Achenia (at least below) and the convex receptade villous. 



8. P. Anserlna, L. (Silver-Weed.) Herbaceous, creeping by slen- 

 der rooting runners; leaves alt radical, pinnate; leaflets 9-19, with minute pairs 

 interposed, oblong, pinnatifid-serrate, green and nearly smooth above, silvery- 

 white with silky down underneath ; stipules many-cleft ; flowers solitary {yeUow), on 

 long scape-like peduncles. Brackish marshes, river-banks, &c., New England 

 to Penn., Wisconsin, and northwai-d. June -Sept. (Eu.) 



9. P. fruticdsa, L. (Shrubby Cinque-foii,.) Stem erect, shrubby 

 (2° -4° high), very much branched; leaves pinnate^ leaflets 5-7, closely crowd- 

 ed, oblong-lanceolate, entire, silky, especially beneath ; stipules scale-like ; 

 flowers numerous {yellow), terminating tlie branchlets. — Bog-meadows; same 

 range as the last. June - Sept. (Eu.) 



10. P. tridtentata, Ait. (Mountain Cinque-foil.) Stems low 

 (4' -6' high), rather woody at the base, tufted, ascending, cymosely several- 

 flowei-ed ; leaves palmate ; leaflets 3, wedge-oblong, nearly smooth, thick, coarsely 

 S-toothed at the apex ; petals white ; achenia and receptacle very hairy. — Bocks, 

 on mountains ; and in Maine near the level of the sea ; shore of Lake Superior 

 and northward. June. 



§3. Styles moderately lateral: petals {shorter than the calyx, ovate-lanceolate) and 

 filaments more or less persistent : disk thick and hairy : achenia glabrous : recepta- 

 cle hairy, convex, at length large and spongy. (Comarum, L.) 



11. P. palnstris, Scop. (Marsh Eive-Fingeb.) Stems ascending 

 from a creeping base (l°-2° high) ; leaves pinnate, of 5-7 lanceolate or oblong 

 crowded serrate leaflets, whitish beneath; flowers somewhat cymose ; calyx (1' 

 broad) dark purple inside; petals purple. Ij, (C6marum palustre, L.) — Bogs, 

 N. England to Penn., Wisconsin, and northward. June -Aug. (Eu.) 



12. FRACiARIA, Tourn. Stkawberkt. 



Flowers nearly as in Potentilla. Styles deeply lateral. Eeceptacle in fruit 

 much enlarged and conical, becoming pulpy and scarlet, bearing the minute dry 

 achenia scattered over its surface. — Stemless perennials, with runners, and with 

 white cymose flowers on scapes. Leaves radical : leaflets 3, obovate-wedge- 

 form, coarsely serrate. Stipules cohering with the base of the petiole, which 

 with the scapes are usually hairy. (Name from the fragrance of the fruit.) — 

 The two species are indiscriminately called Wild Strawberry.) 



1. F. Virgriniaiia) Ehrhart. Achenia embedded in the deeply pitted recep- 

 tacle. — Fields and rocky places ; common. April - June. — Scapes commonly 

 shorter than the leaves, which are of a rather coriaceous or firm texture. Fruit 

 roundish-ovoid. 



