Arthur: Uredinales of Costa Rica 139 



same family of plants, none of which, however, extends into 

 Central America. It has smaller spores with less apical thicken- 

 ing than P. mexicana D. & H. on Pentstemon. In spore measure- 

 ments it is like the northern P. Synthyridis E. & E., on Syn- 

 thyris, but has darker and more crowded sori, while from P. 

 Seymeriae Burr., on Gerardia and Dasystoma it is distinguished 

 by darker and thicker-walled spores. The same species occurs 

 in Guatemala on Castilleja. 



80. Puccinia depallens Arthur & Holway sp. nov. (on 

 Bignoniaceae) 



Pithococtenium muricatum DC. ( ?), road to Volcan de Poas, Jan. 

 5, 1916, O, III, 365. 



Pycnia epiphyllous, gregarious on discolored areas 2-3 mm. 

 across, light brown becoming dark brown, conspicuous, subcuti- 

 cular, lenticular or low conic, 128-160 /x in diameter, 48-77 ft 

 high ; ostiolar filaments wanting ; pycniospores ellipsoid, color- 

 less, 2.5 by 3-4 fx. 



Telia hypophyllous, crowded in circles on spots opposite the 

 pycnia, early naked, oval, 0.2-0.4 mm. long, compact, light cin- 

 namon-brown or cinereous from the germinating spores, rup- 

 tured epidermis inconspicuous; teliospores terete, large, 16-27 

 by 45-96 fx, obtuse or rounded at both ends, slightly or not con- 

 stricted at the septum, which is more or less oblique ; wall color- 

 less or slightly tinted, uniformly thin, 1 /x, smooth ; pedicel half 

 to nearly as long as the spore, colorless, firm, broad, thin-walled. 



A short-cycle rust with quite or nearly colorless teliospores, 

 that germinate at maturity. It occurs also in Guatemala on the 

 same host. 



81. Puccinia Ruelliae (B. & Br.) Lagerh. (on Acanthaceae) 

 Blechum Brownei (Sw.) Juss., San Jose, Jan. 17, 1916, II, 347. 

 Justicia sp., Orotina, Dec. 29, 191 5, II, 316; Cartago, Jan. 20, 

 1916, I, 447. 



A long-cycle rust, cosmopolitan in milder climates, extending 

 northward to the next to last tier of states before reaching the 

 Canadian line in the Mississippi valley. The form on Blechum 

 with which teliospores have only been found in Cuba and Ecua- 

 dor, is usually listed under the name P. Blechi Lagerh., and forms 



