LEIBERGIA, A NEW GENUS OF UMBELLIFER.E FROM 
THE COLUMBIA RIVER REGION, 
By JoHN M. CouLrer and J. N. Rosr. 
A part of the material upon which this new genus is based has been 
in the National Herbarium a half dozen years, and is doubtless to be 
found in many of our herbaria, either undetermined or incorrectly 
named, The receipt of some excellent additional material from Mr. 
W.N. Suksdorf and an abundant supply from one of our field agents, 
Mr. John B. Leiberg, gives the opportunity of separating what has 
appeared to us for some time to be a new genus. 
Leibergia, gen. nov. 8 
Calyx teeth obsolete. Fruit flattened laterally, linear, beaked, glabrous; stylo- 
podium wanting. Carpels only slightly flattened dorsally, with five filiform ribs, 
the two lateral a little more prominent and turned inward; oil tubes small, single 
in the intervals, two on the commissural side. Seed face broad, slightly concave, 
but when dry becoming more or less involute. 
Slender, glabrous, acaulescent plants from small globose tubers: leaves ternately 
divided into long, filiform leaflets; umbels irregular; fruit subsessile; flowers white, 
The affinities of this genus are doubtful. It has much the habit of the bulbous 
Peucedanums of the Northwest, but the lateral flattening of the fruit and the 
absence of wings readily exclude it from that genus, Our plant is very closely 
allied to the two anomalous species, Peucedanum ambiguum and P. leptocarpum, which 
likewise have linear fruit with very narrow lateral wings, and is, perhaps, congeneric 
with them. The dorsal flattening of the fruit has hitherto been considered such an 
important character that it seems best, at least for the present, to base our generic 
distinction on this difference rather than to include these two species in the new 
genus. It also has the habitof Orogenia, but lacks the peculiar carpel of that genus, 
Technically it seems to come near Oreomyrris and Chierophyllum. From the former 
it differs in having a compound umbel, and from the latter principally in its pecul- 
iar habit, obsolete stylopodium, and less prominent ribs. 
Leibergia orogenioides, sp. nov. PLATE XXVII, 
Slender, 1.2 to 5 dm, high: leaves nearly as long as the flowering peduncle; leaf- 
lets 1.0 to 7.5 cm. long, entire or with few teeth or linear lobes: rays of the umbel 
three to ten, very slender, often spreading, very uaequal, 2 to 12 cm, long; umbellets 
with few flowers and fruits; pedicels 2 mm. or less long; involucre wanting: invol- 
ucels three to four, small, somewhat united at base: fruit 8mm. long, flattened lat- 
erally, but terete at base, terete and somewhat beaked at apex. 
Collected by John B. Leiberg in the Santianne Creek bottoms, Cour d’Alene 
Mountains, Idaho, June 24, 1895, at an altitude of 950 meters (No. 1027). Also by 
Mr. W. N. Suksdorf in Spokane County, Washington, in low damp ground along 
ae ded 
volo 
