ROSACE.E. 



51 



12. GEXJM, Linnaeus. 



1. G. macrophyllum, Wild. Flowers yellow: style jointed: akene-tails hooked. 



2. G. triflorum, Pursh. Flowers purplish: stales plumose: akene-tails feathery. 



13. FRAGARIA, Tournefort. 



* Akenes deeply pitted in the depressed-globose fruit. 

 Chilensis, Ehrh, Leaves thick, dark green, shining: flowers large. Coast. 

 Virginiana, Ehrh. Similar: flowers smaller: fruit darker. 



* * Akenes on the surface of the ovoid fruit. 

 Californica, C. & S. Light green thin leaves: petioles not silky, 

 vesca, L. Similar: larger. Perhaps No. 3 is only a variety of this. 



14. POTENTILLA, Linnaeus. 



* Style attached at or helow the middle of the ovary. 



A foot or two high: leaflets 5-9, coarsely serrate: petals yellow or white 1 



Creeping: leaves and peduncles radical: leaflets 7 to many: petals yellow. 2 



Stems stout, rooting at the joints: flowers dark lurid-purple 3 



Shrubby leaflets entire, silky, margins revolute 4 



* * Style attached at or near the top of the ovary: stameiis 20. 

 Alpine or subalpine (altitude 7,000 ft. or more) leaflets an inch long or less. 



Densely white tomentose: leaflets 7 to 13: carpels stipitate 5 



Silky-villouA: leaflets closely pinnate or palmate 8, 9 



CTlal)rous: leaflets 3, broadly cuneiform, 7-9-toothed 11 



In the mountains but mostly lower than 7,000 ft. 



Leaflets 5-15, deeply serrate or pinnatifid 6, 7 



Leaflets 3, toothed above 10, 11 



1. P. glandulosa, Lindley. Petals usually shorter than the calyx. 

 Var. Nevadensis, Watson. More slender: stamens sometimes only 20. 



2. P. Anserina, L. Long runners: leaflets with smaller ones between. Wet places. 



3. P. palustris, Scop. Many iibrous roots: leaves palmate: leaflets seiTate. Swamps- 

 P. iruticosa, L. Much branched: stamens 30: carpels very villous. 



5. P. Breweri, Watson. Leaflets nearly equal, 3-6 lines long: petals large. 



6. P. Plattensis, Xutt. Slender stems 3-12 inches long: leaflets pinnatitid. 



7. P. gracilis, Dougl. Taller, more hairy: leaflets and flowers larger. 

 Var. rigida, ^Vatson. Tall and stout, not tomentose. The common form. 



8. P. dissecta, Pursh. Leaflets pinnatifid or coarsely serrate: tufled-hairy. 



9. P. Wheeleri, Watson. Leaflets cuncate, 3-5 toothcil, G lines long or less. 



10. P. Grayi, Watson. Low stems 3-G-flowered: leaflets 5-7- toothed. 



11. P. gelida, C. A. Meyer. Leaflets larger, broader, end one nearly sessile. 



