PROCEEDINGS 



OF THE 



AMERICAN ACADEMY 



OF 



ARTS AND SCIENCES. 



VOL. XX. 

 PAPERS READ BEFORE THE ACADEMY. 



I. 



A REVISION OF THE NORTH AMERICAN SPECIES 

 OF THE GENUS OXYTROPIS, DC. 



By Asa Gray. 



Communicated May 14th, 1884. 



In the sixth volume of the Proceedings of the American Academy 

 (1863), as an appendix to a revision oi Astragalus^ I made an attempt 

 to classify and characterize our comparatively few species of Oxytropis. 

 In the autumn of 1880, I compared our own materials with those in 

 the Kew herbarium, but, unfortunately, without knowing of Bunge's 

 Species Generis Oxytropis, which was communicated to the Imperial 

 Academy of Sciences of St. Petersburg in November, 1873, and pub- 

 lished in its 3Iemoires, Ser. VII. Vol. XXII., in 1874. Bunge cites my 

 notes, but he had not the means for clearing up the obscurities. Even 

 now, after some examination of most of the originals, I can only par- 

 tially remove them. But the subjoined synopsis n?ay fairly represent 

 our present knowledge. 



OXYTROPIS, DC. 



§ 1. Caulescens, nunc subcaulescens ; stipulis inter se et a petiolo libe- 

 ris : legumen uniloculare calycem longe superans. — Subgen. Pha- 

 coxytropis § Mesogace, Bunge. 

 1. O. DEFLEXA, DC. 0. foUolosa,Y{o6k. (0. foliosa, in Torr. & 



Gray, Fl.), forma subacaulis. — Saskatchewan, and along the Rocky 



Mountains to S. Colorado. (N. Asia.) 



VOL. XX. (N. S. XII.) 1 



