COULTER AND ROSE—NORTH AMERICAN UMBELLIFERAE. 77 
Type species, Seselz divaricatum Pursh, Fl. 2: 732. 1814. 
A group of 4 species, three of which belong to western Canada and 
the United States as far south as Colorado, and one in the high moun- 
tains of southern Mexico. 
Stems dichotomously branching from the base; leaf segments toothed. 
Stems glabrous; fruit smooth, about 4 mm. long.......-..---- 1. M. divaricatum. 
Stems scabrous; fruit scabrous, shorter and broader than in the 
former. ..... 2222-2 eee ee ee ee eee eee 2. M. hookeri. 
Acaulescent, the simple peduncles much exceeding the leaves; leaf 
segments narrowly linear and entire.........--..----------- 3. M. tenuifolium. 
1. Musineon divaricatum (Pursh) C. & R. Bot. Gaz. 20: 259. 1895. 
Seseli divaricatum Pursh, Fl. 2: 732. 1814. 
Adorium lucidum Kuntze, Rev. Gen. Pl. 1: 264. 1891. 
Decumbent, glabrous; leaves bipinnatifid, with winged rachis; seg- 
ments 3 to 5-toothed; peduncles 5 to 12.5 cm. long; umbel 10 to 25- 
rayed; rays 6 to 18 mm. long; pedicels short; fruit smooth, about 4 
mm. long; oil tubes 3 in the intervals, with accessory ones beneath the 
ribs, 4 on the commissural side; seed terete, with rather deeply con- 
cave face. - 
Type locality, ‘Sin upper Louisiana;” collected by Bradbury; type 
in Herb. Philad. Acad. 
From Alberta and Assiniboia to Montana, western Nebraska, and 
Colorado. 
Specimens examined: : 
ALBERTA: Lethbridge, Macoun 4972, June 5, 1894. 
Assrnrpora: Old Wives Creek, Macoun 10658, June 2, 1895. 
Montana: Near Helena, Kelsey 263, in 1889; Great Falls, Williams 16, June 24, 1892. 
Wyomina: Yellowstone Park, altitude 1860 meters, Burglehaus, June, 1893; Lar- 
amie County, Nelson 2875, May 14, 1897; Glen Creek, Yellowstone Park, 
A. & E. Nelson 5568, June 29, 1899. 
Norta Dakora: Fort Buford, Harvard, May—June, 1889. 
South Dakota: Black Hills, Forwood, in 1887; same region, altitude 1050 meters, 
Rydberg 719, June 28, 1892; Alkali Creek, V. Bailey 17, June 3, 1894. 
NEBRASKA: Minden, Kearney County, Hapeman. 
Cotorapo: Near Denver, Alice Hastwood, in 1891; near Windsor, Osterhout, June, 
1894 and 1895; near Denver, Bethel, in 1895 and 1898; near Fort Collins, 
Baker 6, May, 1896. 
2. Musineon hookeri (Torr. & Gray) Nutt. in Torr. & Gray, Fl. 1: 642. 
1540. 
Musenium divaricatum hookeri Torr. & Gray, Fl. 1: 642. 1840. 
M. trachyspermum Nutt. in Torr. & Gray, I. ¢. 
M. angustifolium Nutt. in Torr. & Gray, |. c. 
Resembling Jf. d7varicatum, but more or less scabrous throughout; 
fruit scabrous, smaller, 2 to 3 mm. long, with more prominent ribs; 
oil tubes mostly solitary in the intervals, often with smaller accessory 
ones in the intervals or beneath the ribs, two on the commissural side; 
seed sulcate beneath the oil tubes, with more shallow concavity. 
