106 MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY 



acuminate, green, often 2-3-cleft. Basal leaves pinnate, of many leaflets, sparingly strigose- 

 ciliate, nearly as long as the stems. Stem leaves much reduced ; leaflets divided nearly 

 to the base into linear subulate divisions, which therefore look as if verticillate ; pedi- 

 cels slender, 1-2 cm. long, in fruit abruptly reflexed below the strigose-hirsute hypan- 

 thium. Bractlets and sepals lanceolate, acute, the former slightly smaller. Corolla 1 2- 

 18 mm. in diameter. Petals obcordate, deeply notched, longer than the sepals. Stamens 

 about 20. Achene smooth with a slender filiform nearly terminal style. 



P. miUefulia most resembles P. Plattciisis, but differs in the long and very narrow 

 segments of the leaves, the reflexed fruiting calyx and the longer sepals. The following 

 specimens have been examined : 



CaUfornia: J. G. Lemmon, 1S73; 1S74; No. 86, 1875 (type), and No. 38; E.. L. 

 Greene, No. 750, 1876; J. W. Congdon, No. 277, 1880; T. S. Brandegee, 1887 and 1892; 

 Baker & Nutting, 1894. 



gi. Potentilla Arizonica Greene. 



Icesla pinnatlfida Wats. Proc. Am. Acad. 20 : 364. 1885. Not P. pinnatifida L. 



Potentilla Arizonica Greene, Pittonia, 1 : 104. 1887. 



Illustrations : Plate 4-5, f. 2; dissection of flower after blooming,/. 3; pistil,/. 4; 

 fruiting hypanthium and calyx, /. 5. 



Perennial with a thick woody branched caudex. Stems ascending or erect, a little 

 over 1 dm. high, subscapose, grayish strigose. Leaves nearly all basal, rather irregularly 

 pinnate, with 7-1 2 pairs of leaflets, grayish strigose-hirsute ; leaflets obovate in outhne, 

 divided to near the midrib into 7-9 linear diverging segments. Stipules brown, adnate 

 to the petiole for a long distance, striate. Cyme 5-8-flowered. Hypanthium strigose, in 

 fruit 5-8 mm. in diameter ; bractlets oblong or lanceolate, a little shorter than the ovate 

 sepals. Petals unknown. Stamens 20. 



This was described by AA'atson from fruiting specimens and referred to Iveda. These 

 fruiting specimens, which are the only ones I have seen, show very plainly that the plant 

 is a true Potentilla nearest related to P. pimmimda and P. Richardii. It should not be 

 placed in Ivesia, even if the latter is regarded as a subgenus of Potentilla, as it has all the 

 characters of a true Potentilla. 



Arizona : J. G. Lemmon and wife, 1884 (near Flagstaff). 



92. Potentilla pinnatisecta (Wats.) Aven Nelson. 



Potentilla pinnatisecta Aven Nelson, Wy. Exp. Sta. Bull. 28: 104. 1896. 

 Rydb. Bull. Torr. Bot. Club, 23 : 432. 



