RYDBERG : ASTRAGALUS AND ITS SEGREGATES 659 
genus is represented in Colorado by: A. moilissimus Torr., A. 
Bigelowit A. Gray, A. anisus Jones, A. canadensis L., A. colora- 
densis Rydb., A. nitidus Dougl. (A. adsurgens Hook.; not Pall.), 
A. sulphurescens Rydb., A. virgultatus Sheld. and A. goniatus Nutt. 
3. HAMOSA Medic. Vorles. Churpf. Phys. Ges, 
A370... 47Gs. 
The type of this genus was Astragalus hamosus L. To it 
belongs, beside H. Nuttalliana (DC.) Rydb. and 7. leptocarpa 
(T. & G.) Rydb. already named, also the following : 
Hamosa scaposa (A. Gray) Rydb. 
Astraglus scaposus A. Gray Proc. Am. Acad. 13: 366. 1878. 
4. CYSTIUM Stev. Bull. Soc. Nat. Mosc. 4: 268. 1832. 
This genus was based on Astragalus Cicer L., A. Pallasit 
Sprengel and A. physodes L. Congeneric with these are : 
Cystium diphysum (A. Gray) Rydb. 
Astragalus diphysus A. Gray, Pl. Fendl. 34. 1849. 
Cystium ineptum (A. Gray) Rydb. 
Astragalus inceptus A. Gray, Proc. Am. Acad. 6: 525. 1865. 
5. TIUM Medic. Vorles. Churpf. Phys. Ges. 2: 373. 1787. 
This was based on Astragalus sulcatus L. The typical Color- 
ado species of this genus are: 
Tium Drummondii (Doug!.) Rydb. 
Astragalus Drummondit Dougl.; Hook. Fl. Bor. Am. 1: 153. 
1831. 
Tium racemosum (Pursh) Rydb. ~ 
Astragalus racemosus Pursh, Fl. Am. Sept. 740. 1814. — 
Tium scopulorum (Porter) Rydb. 
Astragalus scopulorum Porter, in Porter & Coult. Syn. Fl. Colo. 
a4. 4074, 
I refer to it also the following, which although not closely 
related to the type fit better in this genus than in any other: 
Tium alpinum (L.) Rydb. 
Astragalus alpinus L. Sp. Pl. 760. 1753- 
