RYDBERG: ASTRAGALUS AND ITS SEGREGATES 665 
Phaca cerussata (Sheld.) Rydb. 
Astragalus cerussatus Sheld. Bull. Geol. & Nat. Hist. Surv. Minn. 
O: £30... 1804 
Phaca Bodinii (Sheld.) Rydb. 
Astragalus Bodinit Sheld. Bull.’ Geol. & Nat. Hist. Surv. Minn. 
9: 122. 1394. 
Sheldon placed this among the Howa/obdi and described the 
pod as being flat, but all specimens with well-developed fruit show 
that the species is a typical Phaca. 
Phaca humillima (A. Gray) Rydb. 
Astragalus humillimus A. Gray, in Brandegee, Bull. U. S. Geol. 
Dury, fer. 3: 236. 1876. 
Phaca elatiocarpa (Sheld.) Rydb. 
Astragalus lotiflorus brachypus A. Gray, Proc. Am. Acad. 6: 
209. 1863. 
Astragalus elatiocarpus Sheld. Bull. Geol. & Nat. Hist. Surv. 
Minn. 9g: 20. 1894. 
Phaca Wetherillii (Jones) Rydb. 
Astragalus Wetherillii Jones, Zoe 4: 34. 1893. 
15. KENTROPHYTA Nutt. in T. & G. Fl. N. Am. £: 353. 
1838. 
Besides the XK. ziridis Nutt., the following are found in 
Colorado : 
Kentrophyta impensa (Sheld.) Rydb. 
Astragalus Kentrophyta elatus S. Wats. Bot. King’s Expl. 77. 
1871. Not A. el/atus Boiss. & Bal. 1849. 
Astragalus viridis impensus Sheld. Bull. Geol. & Nat. Hist. Surv. 
Minn. g: 118. 1894. 
Kentrophyta Wolfii Rydb. 
Homalotus Wolfit Rydb. Bull. Torrey Club 31: 562. 1904. 
Kentrophyta aculeata (A. Nelson) Rydb. 
Astragalus tegetarius implexus Canby, in Porter & Coult 
Colo. Add. (no page-number) 1874 
Astragalus aculeatus A. Nelson, Ball Torrey Club 26: Io. 
1899. 
