no 



long; pciliccls ;} to T) lines loiio-; fruit hroaclh' oliloiio-^ ^yi to 8 lines 

 long, 'i lines broad, with wings half as broad as body, and pron-"!- 

 ncnt dorsal and intermediate ribs: oil-tubes 1 to H in the intervals, 

 2 to 4 on the commissural side. 



From the Saskatchewan to Nebraska, Mibsoiui i Traci/u Kansas {Oijs- 

 ler), Indian Territory and Texas {Rererchoii). Fl. March and April. 



The forms distributed under this name from New Mexico and Arizona 

 are mostly P. riUoKinn. 



10. P. Grayi C. A: R. Hot. Ga/ette. xiii. 20V). Glabrous, 

 with peduncles 12 to 18 inches long: leaves ternate-pinnately de- 

 compound, the ultimate segments linear, elongated or short, cus- 

 pidate, very numerous: umbel rather equally () to KVrayed, with 

 involuccls of distinct linear-subulate bractlcts; rays 1 to 8 inches 

 long; pedicels 5 to H lines long: fruit oblong, 4 to 8 lines long, 

 2^ to 4j/^ lines broad, with wings usually more tiian half as 

 broad as body, and filiform dorsal and intermediate ribs: oil-tubes 

 usually solitary in the intervals (sometimes 2 in the lateral intei'- 

 vals), 2 or 4 on the commissural side. (Fig. 46.) — P. 'fniUcfoliuni 

 Watson, King's Rep. v. 129, a name which must give way to the 

 older P. millefolium of Sonder from S. Africa. 



Common on dry rocks, from N. Utah to Washington Territory. Fl. 

 March to May. 



It has been questioned whether certain forms with short leaf-segments 

 are not entitled to rank at least as varieties, but we find the short and 

 elongated leaf-segments often upon the same plant. When the segments 

 become very much elongated and crowded the leaves strikingly resemble 

 those of Leplotirnia purpurea. 



* * Ploxvcrs ivJiitc. 



11. P. macrocarpum Nutt. Torr. & Gray, Fl. i. 627. 

 Somewhat caulescent or nearly acaulescent, foot or less high, more 

 or less iDubescent, from a long caudex terminating below in a fusi- 

 form tuber: leaves bipinnate, segments pinnately incised, ultimate di- 

 visions ovate or shortly linear: umbel somewhat equally 6 to 8-rayed, 

 with involucels of conspicuous somewhat foliaceous lanceolate or 

 linear biactlets, often united and unilateral; rays 1 to 8 inches long; 

 pedicels 2 to 5 lines long; flowers mostly white (rarely yellow): 

 calyx-teeth evident: fruit narrowly oblong, glabrous, 4 to 12 lines 

 long, 2 to 8 lines broad, with wings about half as wide as body, 

 and filiform dorsal and intermediate ribs: oil-tubes solitary in the 

 intervals (often obscure, rarely 2 or 8), 2 or 4 on the commissural 



