104 MISSOURI BOTANICAL GARDEN. 
umbel not so much branched, and branched rarely at the 
crown; stem leaves more deeply and grossly serrate, more 
spatulate; floral leaves, at least the lower, oblong, even 
the upper ones longer than wide; involucral lobes and 
bracts smooth; seeds purplish brown when ripe, the reticu- 
lations more open and regular.—JIn the Missouri River 
Valley, usually in open prairie or waste places, from Mis- 
souri to South Dakota and west to Colorado and Idaho, and 
extending into eastern Washington. — Plate 18. 
Intergrading with the species proper on the borders of 
their ranges, and though possessing very marked characters, 
it seems best retained under 2. Arkansana. 
Specimens examined from Oklahoma (Blankinship, 1896); Colorado 
(Eastwood, Denver, 1892, 1897); Nebraska (Clements, St. James, 2621, 
1898; Rydberg, Lincoln, 1890; ?Fremont Exped., Little Blue, 1842, per- 
haps a plant of very dry places; Hayden, Red Cedar Island, 1853, with 
large seeds and much like var. Coloradensis); Kansas (Gayle, Ft. Riley, 
631, 1893; Bodin, Lindsborg, 1884; Shear, Osborne Co., 95, 120, 1894; 
Smyth, Hutchinson, 46, 1890; Oyster, Paola, 1883, near the type; Norton, 
Manhattan, 1897; Hitchcock, Courtland, 1892; Kellerman, 1895; Norton 
& Clothier, 481, 1895); South Dakota (Hayden, Ft. Pierre, 1853); Iowa 
(Harvey, Humbolt, 1874; Hitchcock, Iowa City; Parry, Davenport, 
1848); Missouri (Bush, Randolph, 586, 1895; Popenoe, 1875); Idaho 
(Spalding, Clear Water); Montana (Watson, 356, 1880, seeds large; Hay- 
den, Madison River, 1860); New Mexico (Vasey, Las Vegas, 1881); (Dr. 
James, on the Missouri, Long Exped.; Havard, Yellowstone Riv., 1878; 
Stevens, Pac. R. R. Exp.). 
Also reported from Minnesota (Z. dictyosperma), Leiberg, Rock Co. 
(Upham, Cat. Flora Minn. 128, 1884); Moyer, Montevideo (Sheldon, 
Minn. Bot. Studies 1: 588. 1896). 
Many of the northern specimens examined are smaller, 
less branched, the leaves more obtuse, more serrate, and 
in dried specimens of a yellowish color. They are: from 
Idaho (Heller, Lewiston, 3127, 1896; Sandberg, Hatwai 
Creek, 256, 1892; Henderson, Clear Water Riv., 1894; 
Spalding, Clear Water, perhaps from Washington); Mon- 
tana (Kelsey, Helena, 1888; Blankinship, Custer, 70, 1890; 
Allen, Yellowstone Exped., 1873, seeds large); South 
Dakota (Rydberg, Hot Springs, 996, 1892); Washington 
(Brandegee, Wallawalla, 1072, 1883). 
20 
