[Vol. 9 



310 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



1. S. longirostris (Wats.) Rydb. Fl. Rocky Mountains, 364. 



11)17. 



Arabis longirostris Wats. Bot. King's Exp. 17. t. t. 1871; 

 Brewer & Wats. Geol. Survey Calif. Bot. 1: 31. 1876. 



Streptanthus longirostris Wats. Proc. Am. Acad. 25: 125. 

 1889; Wats, in Gray, Syn. Fl. N. Am. I 1 : 170. 1805; Howell, Fl. 

 Northwest Am. 47. 1897; Piper, Contr. U. S. Nat. Herb. 11: 

 296. 1906; Nelson in Coulter & Nelson, Manual Cent. Rocky 

 Mountains, 211. L909; Frye & Rigg, Northwest Fl. 180. 1912. 



r uh I isia longirostris Rydb. Bull. Torr. Bot. Club 33: 142. 

 190G; Rydb. Fl. Colo. 166. 1906; Wooton & Standley, Contr. 



LI. S. Nat. Herb. 19: 269. 1915. 

 Guillenia rostrata Greene, Lean. Bot. Obg. & Crit. 1: 228. 



1906. 



Annual, glabrous and glaucous throughout: stem usually much 



branched above, slender, 3-6 dm. high : leaves deciduous at ma- 

 turity; lower cauline leaves narrowly oblanceolate, usually sinu- 

 ate-dentate or repand, 2-5 cm. long; upper leaves linear-lanceo- 

 late to linear, mostly entire: sepals greenish or tipped with 

 purple, the lateral pair saccate at the base, dorso-ventral pair 

 slightly so, all nearly equal, 3-6 mm. long; petals yellowish, 

 linear-spatulate, exceeding the sepals by about one-fourth; fila- 

 ments tetradynamous, linear, about as long as the sepals, anthers 

 apiculate, about 1 mm. long; nectar glands well developed at 

 base of solitary stamen: inflorescence lax, shortly racemose, 

 elongating in fruit; pedicels soon becoming recurved, slender, 



long: pods pendent, strongly compressed, sessile, 3-6 

 cm. long, 1-2 mm. wide; style very short or obsolete, stigma 

 nearly entire: seeds narrowly winged, flat. 



Distribution: southwestern to central Wyoming, western Colo- 

 rado, northern New Mexico, Utah, Arizona, Nevada, southeastern 

 Washington, eastern Oregon, eastern and southern California, 

 and northwestern Mexico. Type: Watson 72 from "Steamboat 

 Springs near Washoe City, about Humboldt Lake, Nevada." 



Specimens examined: 



Wyoming: Alcova, Natrona County, July 1, 1901, Goodding 

 169 (Mo. Bot. Gard. Herb.); sandhills in Wind River Valley, 

 May 19, 1860, Hay den (Mo. Bot. Gard. Herb.) ; Point of Rocks, 

 June 1, 1897, Nelson 3082 (Mo. Bot. Gard. Herb.). 



Colorado: Grand Junction, May, 1891, Eastwood (Bethel 

 Herb.) ; Grand Junction, May, 1892, Eastwood (Mo. Bot. Gard. 

 Herb.); Naturita, May 7, 1911, Pay son 280 (Mo. Bot. Gard. 



mm 



