Notes on Potentilla.— V. 



By P. A. Rydberg. 

 (Plates 276, 277.) 



The Subviscosae is a small group of low plants with many more 

 or less spreading branches from the caudex, with a silky or hir- 

 sute pubescence, often intermixed with almost sessile glands, but 

 not at all tomentose ; with digitate leaves of 5-7 leaflets, and in fruit, 

 with incurved sepals which enclose the large, but comparatively 

 {t\N achenes. The petals are more or less contracted at the base, 

 I. e., semi-unguiculate, although indistinctly so in P. Wheelen. 



Potentilla Wheeleri Wats. Proc. Am. Acad. 11: 148. 1876. 



The pubescence is quite densely silky, and the typical form is 

 apparently without glands. The leaflets are obovate and crenate 

 at the rounded summit, 1-1.5 cm. long. The petals are obcor- 

 date, slightly contracted at the base, and a little exceed the 

 calyx. It has been collected in southern California, Arizona and 

 northern Mexico. A form connecting it with the next may be 

 regarded as a variety or perhaps as a distinct species. It may be 

 known for the present as 



Potentilla Wheeleri viscidula n. v. 



Subcaespitose, rather hirsute with spreading hairs, somewhat 

 glandular-granuliferous on the calyx, pedicel, etc.; leaflets shorter 

 and broader,* geniorally less than i cm. long. 



The following specimens have been seen : 



Arizona: C. G. Pringle, 1881 ; J. G. Lemmon, no. 158. 1881. 



