MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY 25 



curved in fruit and enclosing the comparatively few and large achenes. Style filiform 

 and very slender. 



A small group related to the Aureae, Concinnae and Graciles. 



Petals not unguiculate, plant silky-Adllous. 29. P. Wheeleri. 

 Petals unguiculate ; plant hirsute and glandular puberulent. 



Leaflets 1-4 cm. long. 30. P. suhviseosa. 



Leaflets 5-7 cm. long with prominent veins. 31. P. ramulosa. 



§8. AUREAE. 



Perennials with an ascending short scaly rootstock. Stem (in ours) rather simple, 

 ascending or erect, few-flowered. Leaves digitately or pinnately 5- (seldom 7-) foliolate, 

 in the latter case with approximate leaflets. Pubescence scant, silky-strigose, or hirsute, 

 not at all tomentose (or rarely slightly so in P. dissecta). Petals yellow, obcordate, 

 exceeding the sepals. Bractlets and sepals not incurved in fruit. Style filiform. 



The plants much resemble the Frigidae, but have more leaflets. P. disseda connects 

 the group with the Graciles, which they resemble except as to the size of the plant, and 

 P. multiseda connects it with the 3IiUtijagae. Most of the species belonging to this group 

 have truly digitate leaves, but in the North American representatives the outer leaflets 

 are often inserted lower down and the leaves become pinnate with approximate leaflets. 



Leaflets almost linear, 3-toothed at the apex. 32. P. Sierrae-Blancae. 

 Leaflets obovate, merely crenate. 



Leaves thick, short-petioled (Mexican). 33. P. ranuneuloides. 



Leaves thin, the basal ones with slender petioles (Arctic). 34. P. maculata. 



Leaflets coarsely serrate with acute teeth. 35. P. dissecta. 



Leaflets diAdded about f to the midrib into oblong or lanceolate rather 

 obtuse segments. 



Leaves rather firm with prominent ribs. 36. P. deourrens. 



Leaves thin ; nerves not prominent. 37. P. Ranunculus. 



Leaves divided to near the midrib into linear segments. 38. P. multisecta. 



§ 9. GRACILES. 



Tall perennials (except depauperate specimens), over 2 dm., generally over 3 dm. 

 high, with open rather few-flowered cymes. Leaves digitately ( in P. pulcherrima often 

 pinnately) 5-9-foliolate. Petals obcordate, exceeding the sepals by a third or more. 

 Style in most long, slender and filiform (in P. sulphurea rather short and stout). Sta- 



