OF ARTS AND SCIENCES : MAY 13, 1873. 557 



larger and more distant leaflets is P. Drumriiondii, Lehm. A subdigi- 

 tate form with the leaflets linear-parted is var. multisecta, Watson. 

 P. rubricaulis, Lehm., appears to be a form with the leaflets subtomen- 

 tose beneath, a case of rather rare occurrence. 



Var. decurrens. Leaflets but three or with 1-2 additional dis- 

 tant pairs of smaller ones, the terminal leaflet cuneate-oblong, truncately 

 3-toothed, the upper pair 2 - 3-toothed, conspicuously decurrent, the 

 lowest lanceolate and mostly entire ; stem 1-flowered, 3' high ; glabrous 

 throughout, excepting the villous calyx and tufted apices of the leaves. 

 — 329 Watson, from peaks of the Uintas, at 12,000 feet altitude. A 

 very peculiar form, perhaps distinct. 



f f Leaves digitately 5 - 7-foliolate (rarely pinnate in P. gracilis) ; 

 tomentose or villous. 



15. P. gracilis, Dougl. (P. Blaschkeana, Turcz.) Villous and 

 more or less tomentose ; stems 2-3° high ; stipules ovate or lanceo- 

 late, entire or subincised ; leaflets mostly 7, sometimes 5, very rarely 

 but 3, cuneate-oblong, obtuse, incisely serrate or pinnatifid, tomentose 

 beneath, green above and subvillous or appressed-silky, 1 - 2^' long ; 

 flowers in a loose subfastigiate cyme, the pedicels at length elongated 

 and slender ; calyx with the narrow bractlets shorter than the broad 

 acute or lanceolate sepals ; petals broadly obcordate, 3 - 4" long, a 

 little exceeding the calyx; carpels very numerous (40 or more). — 

 From the Saskatchewan to Southern Alaska, and southward to New 

 Mexico, Utah, and California. The leaflets occasionally show a ten- 

 dency to a pinnate arrangement, and the species is distinguishable from 

 the digitate form of P. Hippiana, var. pulcherrima, only by the more 

 numerous carpels and the usually fewer and more deeply incised leaf- 

 lets. Specimens like 159 Hall & Harbour tend to unite the two 

 species. 



Var. flabelliformis. (P. flabelliformis, Lehm.) Differing only 

 in the more deeply pinnatifid leaflets. 



Var. fastigiata (P. fastigiata, Nutt., P. olopetala, Lehm.) is a 

 form, often low, with a shorter and more crowded cyme, the pubescence 

 more dense and silky, especially upon the calyx and short pedicels. 



Var. rigida. {P. rigida, Nutt., not Wall. P. Nuttallii, Lehm.) 

 A mostly stout and tall form, villous but without tomentum, the cyme 

 loose or crowded, the leaves often large, 3-4' long or more, and promi- 

 nently veined beneath. — The leaves are occasionally decidedly pin- 

 nate, as in 1G2 Hall <fc Harbour. Certainly but a variety of P. gracilis. 



