130 



Mycologia 



Pycnia amphigenous, crowded in small groups, noticeable, sub- 

 epidermal, globoid or slightly flattened, 96-160 ^ in diameter. 



Aecia amphigenous surrounding the pycnia, rather inconspicu- 

 ous, 0.2-0.4 mm. in diameter, deep-seated, over-arched by two 

 or more layers of host cells which tardily rupture by a short slit 

 or pore ; peridium wanting, but sometimes replaced by a thin 

 layer of mycelium ; aeciospores globoid to broadly ellipsoid, 18- 

 23 by 1 9-24 il\ wall colorless, thin, 1-1.5/x, closely and finely 

 verrucose. 



Uredinia hypophyllous, scattered, oval or oblong, 0.4-1 mm. 

 long, rather tardily naked, at first opening by a slit or pore, 

 pulverulent, yellowish, ruptured epidermis conspicuous ; ure- 

 diniospores broadly ellipsoid or obovoid, 18-21 by 23-28 fx; wall 

 colorless, thin, 1— 1 .5 /x, finely and closely echinulate, the pores 

 obscure. 



Telia hypophyllous, scattered, oval or oblong, 0.3-0.8 mm. long, 

 rather early naked, somewhat pulverulent, white, ruptured epi- 

 dermis evident; teliospores oblong to fusiform-oblong, 16-23 by 

 42-64 fi, rounded or acute at both ends, or sometimes narrowed 

 below, slightly constricted at septum, germinating at maturity ; 

 wall colorless, thin, 1 /x, sometimes thickened at apex or side, 

 3-4 fx, smooth ; pedicel colorless, somewhat fragile, half length of 

 spore or less. 



A very distinct species with Erio sporangium-like, characters, 

 the first such species to be found on monocotyledonous hosts. 

 The aecia are easily overlooked. The type selected is a collec- 

 tion on B. acutifolia Herb, made by Professor Holway in Guate- 

 mala, Volcan de Agua, Dept. Sacatepequez, March 7, 1916, O, I, 

 II, III, 562. 



53. Puccinia Polygoni-amphibii Pers. (on P olygonaceae) 



Persicaria punctata (Ell.) Small {Polygonum punctatum Ell.), 

 San Jose, Jan. 8, 1916, II, 395. 

 A widespread species, only forming uredinia as a rule in the 

 tropics. 



54. Puccinia detonsa Arthur & Holway sp. nov. (on 

 Caryophyllaceae ) 

 Stellaria ovata Willd., San Jose, Dec. 11, 191 5, 252. 



Telia hypophyllous and caulicolous, more or less confluent in 

 round or elongate masses 1-2 mm. across on indefinite discolored 



