PEUCEDANUM. UMBELLIFER^E. 257 



P. Isevigatum Nutt 1. c. 627. Caulescent or acaulescent, 6-15 inches 

 high, glabrous, from shallow seated long roots: leaves triternate.; leaflets 

 linear 3-12 lines long by half a line wide : umbel unequally 10-L4-rayed, 

 with involucels obsolete or rarely 1-3 small triangular bractlets : pedicels 

 4-5 lines long : fruit 4-5 lines long 1)^-2 lines broad, with narrow wings 

 and prominent dorsal and intermediate ribs : oil-tubes 2 on the commis- 

 sure : seed-face more or less concave with central longitudinal ridge. On 

 bluffs of the Columbia River, near Celilo. 



* * Leaves with lanceolate or orbicular segments. 



P. leiocarpnm Nutt 1. c 626. Acaulescent, glabrous, 1-2 feet high, 

 from a very long fleshy root : leaves biternate or triternate or ternate- 

 quinate, sometimes simply ternate; leaflets thickish, from ovate to nar- 

 rowly lanceolate 1-2 inches long, petiolulate, entire, or toothed at the 

 apex : umbel very unequally 6-15-rayed without involucels ; peduncles 

 and rays dilated at summit: rays 1-8 inches long: pedicels variable 1-9 

 lines long : flowers yellow : fruit narrowly oblong J5-7 lines long l>-2> lines 

 broad narrowly winged : oil-tubes large and solitary in the intervals, 4 on 

 the commissure : seed-face somewhat concave. Brit. Columbia to Cali- 

 fornia and Idaho. 



P. Nuttallii Watson Bot. King. 128. Acaulescent, glabrous, 6-12 

 inches high : leaves once or twice ternate with ovate to orbicular leaflets 

 with cuneate or cordate base ; fruit ovate to oblong, 4 lines long, 3 lines 

 broad, very narrowly winged: oil-tubes small, 3 in the intervals, 4 or 6 on 

 the commissure : seed-face almost plane. Eastern Oregon to N. Nevada 

 and Idaho. 



P. Brandegei C. & R. Bot. Gaz. xiii, 210. Short caulescent, glab- 

 rous, 6-12 inches high from a thick elongated root; leaves ter- 

 nately decompound the ultimate segments lanceolate, 6-12 lines 

 long, "cuspidate: umbel 6-1 2-rayed, with involucels of few linear or seta- 

 ceous bractlets : rays 3-^6 lines long ; pedicels not more than a line long, 

 both reflexed at maturity : flow T ers yellow : calyx-teeth evident : fruit (im- 

 mature) oblong, about 4 lines long, 2 lines broad, with wings about half 

 as broad as the body, and prominent dorsal and intermediate ribs : oil- 

 tubes 2-4 in the intervals 4 or 6 on the commissure. Near Walla Walla, 

 Washington. (Brandegee.) 



* * * Very stout and tall with large decompound leaves and linear 

 oblong segments. 



P. Suksdorfli Watson Proc. Am. Acad. xx, 369. Caulescent, 2-4 feet 

 high : leaf -segments 1-2 inches long, entire or 2-3-cleft at the top : umbel 

 somewhat equally 6-12-rayed with involucels of linear acuminate bractlets; 

 rays 1-5 inches long ; pedicels 3-9 lines long : flowers yellow : fruit nar- 

 rowly oblong, 9-14 lines long 3-6 lines wide with wings narrower than the 

 body, and very prominent dorsal and intermediate ribs : oil-tubes solitary 

 in the intervals, very large, 2 on the commissure : seed-face somewhat 

 concave. Dry rocky mountain sides, Klickitat county, Washington. 



VII. Low shortly caulescent or acaulescent, from a thick elong- 

 ated root, glabrous : leaves ternate or pinnate with broad oblong or 

 round coarsely cuspidate-toothed leaflets, flowers yellow : fruit-wings 

 verv broad, often several times broader than the body : oil-tubes 3-4 

 or solitary in the intervals. 



P. Howellii Watson 1. c. Short caulescent, peduncles 12-15 inches 

 high : leaves biternate to biquinate : leaflets cuneate-orbicular to round- 

 cordate, acutely dentate, often 3-lobed, 6-12 lines long : umbel with elong- 

 ated and divaricate fertile rays with involucels of acuminate lanceolate 



