127 
we propose for it a new genus, the name of which indicates its changing 
history. 
•49. ZIZIA Koch, Umbel. 120. — Smooth perennials (1 to 3 
feet high), with mostly Thaspium-like leaves, no involucre, invol- 
iicels of small bractlets, yellow flowers, and central fruit of each 
umbellet sessile. — Flowers in early spring, in open prairies and 
upland meadows. 
In separating the species of Zizia from the Tlmspium aureum group 
we are indebted to Mr. M. S. Bebb for his field notes. His observations 
concerning their decided differences in habitat and time of blooming very 
strongly confirm the differences discovered in fruit structure. 
1. Z. aurea Koch, 1. c. Radical leaves very long-petioled, 
all but the uppermost leaves 2 to 3-ternate; leaflets ovate to lanceo- 
late, sharply serrate: rays 15 to 25, stout, ] to 2 inches long: fruit 
oblong, about 2 lines long, (Fig. 148.) — lliaspium aureum^ var. 
apterum Gray, Manual, 195. Carnm aureum Benth. & Hook. 
Gen. Plant, i. 891. 
Throughout Canada and the Atlantic States, extending westward as 
far as Saskatchewan and Texas. 
Although Tkaspium aureum var. aptermu is the real synonym of the 
species, botanists will find in their herbaria many specimens of Zizia 
aurea labeled Tkaspium aureum anti T. trifoliaiutn. 
Var. Bebbii C. & R. Bot. Gazette, xii. 138. A more slender 
mountain form, with leaflets more coarsely serrate or even toothed, 
the radical leaves smaller and more simple: rays 2 to 8, slender, 
2 to 3 inches long: fruit mostly smaller, oval, 1 to li.^ lines long. 
West Virginia {Canby), Virginia, N. 
Cauby, Meehan, Farter), and Georgia ( Va.sc 
Carolina {Buckley, Curtiss, 
!))■ 
2. Z. COrdata Koch, 1. C. Radical leaves mostly long- 
petioled, cordate or even rounder, crenately toothed, very rarely 
lobed or divided ; stem-leaves simply ternate or quinate, the leaf- 
lets ovate to lanceolate, serrate, incised, or even parted: fruit ovate, 
l]4, lines long: seed-section larger than the preceding. (Fig. 149.) 
— 'rhaspiiun trifoliatuni, var, apterum Gray, Manual, 195. 
Carum cordaium Benth. & Hook. Gen. Plant, i. 89 
Same range as last and extending to Oregon, 
As in the last species, herbarium specimens of Zizia cordata will be 
found labeled almost anything under the Tkaspium aureum section. 
