154 
BRASSIACEAE. 
6. DITHYREA Harv. 
i. Dithyrea Wislizeni Engelm. In dry regions from Tex. and Colo, to 
Utah and Ariz.—Alt. 4500-6000 ft.—Valley of the San Juan (Brandegee ). 
7. PHYSARIA A. Gray. Double Bladder-pod. 
Pods deeply cordate at the base; lower sinus almost as deep as the upper. 
1. P. didymocarpa. 
Pods not cordate at the base or slightly so ; lower sinus none or very shallow. 
Basal leaves or at least some of them more or less fiddle-shaped. 
Leaves of the decumbent flowering stems reduced ; terminal lobe of the basal 
leaves rounded or reniform, very obtuse, entire. 2. P. •vitulifera. 
Leaves of the ascending flowering stems ample; terminal lobe of the basal 
leaves rhombic or ovate, obtuse or acute, sinuate. 3. P. floribunda. 
Basal leaves oblanceolate or spatulate, acute, not fiddle-shaped, 2-4 cm. long. 
4. P. acutifolia. 
1. Physaria didymocarpa (Hook.) A. Gray. On dry hills from Sask. and 
Alb. to Colo, and Utah.—Alt. 5000-7000 ft.—Bluffs north of La Porte; Ft. 
Collins; Ruxton; Durango; Mancos. 
2. Physaria vitulifera Rydb. In mountain valleys and canons of Colo.—■ 
Alt. 8000-10,000 ft.—Palisades; Idaho Springs; Grand Junction; headwaters 
of Clear Creek; alpine ridges east of Middle Park; Bear Creek Canon. 
3. Physaria floribunda Rydb. In mountain valleys of Colo.—Alt. 5000- 
9000 ft.—Plains and foot-hills near Boulder; Wolcott; Veta Pass; Golden, 
Jefferson Co.; Cimarron; Sangre de Cristo Creek; Clear Creek Canon; 
Hotchkiss; Eldora to Baltimore. 
4. Physaria acutifolia Rydb. On dry hills in Wyo. and Colo.—Alt. 5000- 
10,500 ft.—Grand Junction; Ruxton Ridge; North Cheyenne Canon; Steam- ’ 
boat Springs. 
8. LESQUERELLA S. Wats. Bladder-pod. 
Ovary and pod stellate-pubescent. 
Pods ovoid or ellipsoid. 
Pods distinctly compressed and acute at the apex. 
Pods 6-8 mm. long; plant usually over 1 dm. high. 
Basal leaf-blades broadly oval; septum elliptic in outline; style equalling 
the pod in length. 1. L. Shearis. 
Basal leaf-blades oblanceolate to obovate; septum ovate in outline; style 
much shorter than the pod. 2. L. curvipes. 
Pods 3-5 mm. long; plant 1 dm. or less high. 
Leaves narrowly linear-oblanceolate ; plant pulvinate. 3. L. alpina. 
Leaves narrowly linear; plant multicipital with a subterranean woody 
caudex. 4. L. parvula. 
Pods not compressed above. 
Basal leaf-blades rounded or broadly spatulate. 
Stem-leaves small, generally less than 1 cm. long, linear-oblanceolate. 
5. L. prostrata. 
Stem-leaves oblanceolate to obovate, 1-2 cm. long. 6. L. montana. 
Basal leaf-blades linear-oblanceolate. 7. L. arenosa. 
Pods globose. 
Stem very slender; stem-leaves oblanceolate, 1-3 cm. long. 
7. L. arenosa. 
Stem stouter, strict; stem-leaves linear, 2-6 cm. long. 8. L. argentea. 
Ovary and pod glabrous, globose. 
