COULTER AND ROSE—-NORTH AMERICAN UMBELLIFERAE. 85 
Perennial, from a branching caudex; involucre of 3 to 5 unequal bracts; involucels 
of 5 to 8 rather small ovate bractlets; carpel with prominent ribs; oil tubes con- 
tinuous about the seed cavity, and one in each rib; seed face plane. 
1. B. americanum, 
Annual; involucre none; involucels of 5 very conspicuous ovate mucronate bractlets; 
carpels with very slender ribs and no oil tubes; seed face somewhat concave (see 
p. 252)......2.-22-.2---2-2-2------ 22-222 B. rotundifolium. 
1. Bupleurum americanum ©. & R. Rev. N. Am. Umbell. 115. 1888. 
Fic. 17. 
Basal leaves linear-lanceolate; cauline ones very variable, oblong to 
linear, more or less clasping; rays unequal, 1.5 to 5 em. long; pedicels 
short. 
From Alaska to Montana, Idaho, and Wyoming. 
Specimens examined: 
ALASKA: Fort St. Michael, Norton Sound, Bannister, in 1865-66;.same_sta- 
tion, Turner 8, August 14, 1879; Herald Island, Captain Hooper, in 1881; 
above Fort Yukon, Bates, in 1881; Funston 147, in 1893; Yukon region, 
Wilhams, in 1899; Yakutat Bay, Saunders 4114, July 12, 1899. 
ALBERTA: Waterton Lake, Macoun 10670, July 28-31, 1895. 
Montana: Valley of Musselshell River, Canby, August 19, 1882; Belt Mountains, 
Anderson, September, 1889; same station, Williams 197, September 7, 1890; 
near Red Lodge, Rose 46, July 27, 1893; Beartooth Mountains, above timber 
line, V. Bailey 37, August 13, 1894; near Geyser, Cascade County, Ward 140, 
August 27, 1895; Spanish Basin, Madison Range, altitude 1,800 meters, 
Flodman 682, July 11, 1896; Little Belt Mountains, altitude 1,800 meters, 
Flodman 683, 684, August 16-18, 1896. 
Ipano: Mountains at head of Redfish Lake, 
altitude 2,550 to 3,000 meters, Hrerimann 
446, August 22, 1895, 
Wyomine: Coulter, in 1872; Green River, 
Richardson, in 1878; mountains of Yel- 
lowstone Park, Anowlton, August 15, 
1887; Mvermann, in 1893; north-western 
Wyoming, Mose 341, September 6, 1893; 
Teton Mountains, Nelson 972, August 21, 
1894; Union Pass, Ve/lson 893, Angust 14, 
1894; Electric Peak, Yellowstone Park, 
Rydberg 4600, August 18, 1897. 
For introduced species, see page 252. 
19. TREPOCARPUS Nutt. in DC. Coll. 
Mém. 5: 56. L829, Fic. 18.—Trepocarpus aethusae: 
a, 12: By 10. 
Calyx teeth prominent, unequal. Fruit . 
linear-oblong, flattened laterally, smooth. Carpel somewhat dorsally 
flattened, with no primary ribs, 4 prominent corky secondary ribs, 
and a broad conspicuous band of strengthening cells about the seed 
cavity, making a thick crustaceous pericarp. Styvlopodium conical, 
with very short style. Oil tubes solitary beneath the secondary ribs, 
