212 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
with very narrow wings, and filiform or almost obsolete dorsal and 
intermediate ribs; oil tubes (sometimes wanting) very obscure, 8 to 6 
in the intervals, 1 in each rib, and 6 on the commissural side; seed 
face plane. 
Type locality, on denuded hilltops near *‘Alkali,” Oregon; collected 
by Howell, no, 8380, May 20, 1882; type in Herb. Coulter, duplicate 
in U.S. Nat. Herb. 
Mountains of Oregon and Washington. 
Specimens examined ¢ . 
OREGON: Type specimens as cited under type locality; Trout Creek, Bine Moun- 
tains, Howell, May 25, 1885. 
WASHINGTON: Simcoe Mountains, //owel/ 180, June, 1881; mountains near 
Columbus, Klickitat County, Suksdorf 1207, April 13, 1886. 
Our original description of this species included a second form which Mr. Howell 
well separated as Peucedanum gormani. 
8. Lomatium ambiguum (Nutt.) C. & R. 
Eulophus ambiquus Nutt. Jour. Philad. Acad. 7: 27. 1884. 
Peucedanum ambiguim Nutt. in Torr, & Gray, Fl. 1: 626. 1840. 
Glabrous, from low acaulescent to 3 dm. high and caulescent, with 
tuberous sometimes moniliform roots; petioles much dilated at base; 
leaves once to twice pinnate, with more or less elongated linear leaf- 
lets, the upper often more dissected: umbel unequally 8 to 18-rayed, 
with no involucels; rays 2.5 to 8.5 em. long; pedicels 4 to 8 mm. long: 
flowers yellow; fruit narrowly oblong, glabrous, 6 to 8 mm. long, 
2 mm. broad, very narrowly winged; oil-tubes solitary in the inter- 
vals, 2 (broad and thin) on the commissural side. 
Type locality, ‘on the borders of Flat-Head River.” Oregon; col- 
lected by Wyeth, type in Herb. Philad. Acad. 
From eastern Oregon to British Columbia, and eastward to Mon- 
tana and western Wyoming. 
Specimens examined: 
OrkGON: Type specimens as cited under type locality; Geyer 298; Blue Moun- 
tains, Verius, in 1873 and 1874; Union County, Cusick 1099, May-June, 1883; 
Henderson 55, June, 1886; Sheldon 8308, in 1897; Cusick 2188, in 1898. 
Wasuinecron: Hills near Spokane, Lya//, in 1861; eastern Washington, G. R. 
Vasey 15, in 1883; Spokane County, Suksdorf 319, June 19-28, 1884; GR. 
Vasey 298, in 1889; Spokane County, Henderson 392, June-July, 1892; Pull- 
man, Piper 1562, July 20, 18938; Sandberg & Leiberg 22, 44, 481, in 1893; 
Wenatchee, Whited 61, May 6, 1896; Spokane and Blue Mountains, Walla- 
walla County, Piper 2299, 2337, May-August, 1896; Blue Mountains, Horner 
220, July 29, 1897; Pullman, Whitman County, Elmer 827, May, 1897. 
Britisn CotumBia: Yale, Macoun, May-July, 1889. 
Ipano: Kootenai County, Leiberg 551, June, 1890; Lake Pend Oreille, Leiberg 
637, May-July, 1891; along Peter Creek (Nez Perces County) and valley of 
Spokane River (Kootenai County), Sandberg 125, 659, May-July, 1892; 
Clearwater River, Henderson, June, 1894: St. Marys River, Leiherg 88, June 
27, 1895) Lewiston, Nez Perces County, A. A. & EL Gertrude Heller 2995, 
April 30, 1896; Priest River, Leiherg 2817, August 4, 1897; Salubria and 
Indian Valley, Jones, July 10-13, 1899, 
