THECOPSORA 



369 



Credo Padi K. et S. exsicc. 187. Cooke, Handb. p. 527. 



U. porphyrogenit.i Kze. ; Cooke, Micr. Fung. p. 21(5. 



Melampsora Padi Cooke, Handb. p. 523 (1871). Plowr. Ured. p. 246. 



Fung. Fl. Yorkshire, p. 184. 

 Pucciniastrum Padi Dietel in Eng. u. Prantl, NatUrl. Pflanz. i. 1**, 



p. 47. Fischer, Ured. Schwciz, p. 463, f. 303 ; Centralbl. f. 



Bakter. 2. xv. 227. 

 Thecopsora areolata Magn. in Hedwigia, 1875, p. 123. Sacc. Syll. 



vii. 764. 



Spermogones. Whitish, pustular, flat, open, exhaling a 

 strong smell. 



sEcidiospores. yEcidia crowded, covering on the upper 

 (sometimes the under) side the lower 

 part of the scales of the fallen cones, 

 hemispherical or polygonal; peridium 

 thick, brown, woody, opening by a 

 slit; spores oval, inequilateral, yellow, 

 21 — 28x17 — 20 /x ; epispore very 

 thick (up to 6 /j.), echinulate, with a 

 narrow, thinner, smooth stripe. 



Uredospures. Sori hypophyllous, 

 clustered on spots 1 — 5 mm. wide 

 which are brownish above, reddish 

 or purplish below, and more or less 

 bordered by the veins, covered by the 

 epidermis and by a peridium which 

 opens at the summit by a pore ; spores oblong-oval or irregular, 

 echinulate, pale-yellowish, 15 — 21x10 — 14 //,; epispore about 

 H/a thick. 



Teleutospores. Developed in the epidermal cells, several in 

 each, epiphyllous or occasionally hypophyllous, forming dark- 

 brown shining crusts which are bounded by the veins ; spores 

 oval-cylindrical or prismatic, 22 — 30 x 8 — 14 /*, divided by thin 

 longitudinal walls into 2 — 4 cells ; epispore thin, slightly 

 thickened above, clear-brown, smooth, with a germ-pore in the 

 upper and inner corner of each cell.. 



iEcidia on cones of Picea excelsa, Scotland, Yorkshire, 

 August, November; uredo- and teleutospores on Prunus Padus,, 

 August, September. Very rare. (Fig. 276.) 



g. u. 24 



Fig. 276. Th. Padi. a, leaf 

 of P. Padus, showing uredo- 

 sori ; b, scale of cone of Picea 

 excelsa, showing aecidia (both 

 reduced). Some of thesecidia 

 are broken and empty. 



