iQ2o] BISBY—UROMYCES 205 



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o . 2-0 . 7 mm. across, early naked, pulverulent, chocolate-brown, 



surrounding epidermis at first evident, later often hidden by the 



loose spores; teliospores ellipsoid or irregularly obo void, 21-26 X 



27-40 fi (sometimes variable in size, and larger), rounded above, 



rounded or narrowed below; wall chestnut-brown, 1.5-3 M thick, 



apex 3-5 /x thick, often with a slight umbo over the pore, smooth; 



pedicel colorless, delicate, fugacious, half as long as the spore or 

 less. 



On Fabaceae: Psoralea physodes Dougl., California, Washington, British 

 Columbia; P. Purshii Vail, Nevada. 



Type locality: Winnemucca, Nevada, on Psoralea Purshii. 



Distribution: Pacific Coast region, west of the mountains, from British 

 Columbia to California. 



Exsiccati: Barth., N.Am. Ured. 1582; D. Griff., W.Am. Fungi jgo; 

 Barth., Fungi Columb. 4884. 



The type of this species is Griffith's West American Fungi 

 390, which was issued as Uromyces Psoraleae Peck. U. Psoraleae 

 possesses aecia, however. U. abhrcviatus, while without aecia, 

 and possessing pycnia with the telia, resembles U. Psoraleae in the 

 telial stage, as indicated by Arthur in the notes with the original 

 description. While U. Psoraleae extends to the Pacific Coast, it 

 is more common in the Rocky Mountain region, and extends over 

 the plains to the east of the mountains. U. abbreviatus, so far as 

 known, is limited to the region west of the Rockies. 



There is an unconnected Aecidium (Aecidium onobrychidis 

 Burrill, Bull 111. State Lab. Nat. Hist. 2:225. 1885) upon Psoralea 

 Onobrychis, represented as far as known by the one collection by 

 Seymour in Illinois, and distributed by Ellis and Everhart as 

 North American Fungi 1826. No other species of rust are reported 

 for the genus Psoralea, and these species are only known in North 

 America. Related hosts, as given by Engler and Prantl, except 

 for the genus Indigofera in an adjoining section, are scarcely known 

 to be attacked by rusts; no closely related rusts are evident upon 

 related hosts. 



While the type collection is from an altitude of about 5000 ft., 

 other collections in the Arthur herbarium are from nearer the coast 

 at much less altitude, extending almost down to sea-level. 



