314 CRONARTIUM 



C. flaccidum Wint. Pilze, i. 236 1884). Plowr. Ured. p. 254. Sacc. 



Syll. \ii. 598. 

 Peridemiium Cornui Kleb. Zeitschr. f. Pflauzenkr. L892, ii. 269, pi. 5, 



f. 2. 



/Ecidiospores. /Ecidia (P. Cornui) erumpenl from the bark, 

 forming large reddish-yelkm Madders, generally occupying a 

 portion of a branch in large numbers : spores ellipsoid, 'I'l — 26 

 x 16 — 20 /a; epispore 3 — 4 \x thick, verrucose, thinner od part 

 of its surface and there smooth or somewhat reticulate. 



Uredospores. Sori small, pustular, surrounded bya peridium 

 which opens at the summit with a pore; spores ellipsoid or 

 ovate spai Immlate. 21 — 24x17 — 21 fi. 



Fig. 238. C. asclepiadeum. n. Peridermium Cornui on branch of Pine; 

 h, teleuto-sori on leaf of Peony (reduced); c, uredospore x 600 ; d, part 

 of a column of teleutospores x 300. 



Teleutospores. Sori cylindrical, often curved, arranged in 

 large clusters, over 1 mm. high, brown, at length horny, 

 compact; spores ellipsoid or cylindrical-oblong, reaching 5G /u. 

 long and 14 /j, broad; epispore thin, slightly thicker above. 



.Keidia on the branches of Pinus silvestris, May, June; 

 uredo- and teleutospores on Paeonia officinalis in gardens, 

 July — October. Very uncommon. (Fig. 238.) 



It has been proved by the researches of Cornu, Klebahn, Fischer and 

 many others, not only that the remarkable eecidia on Pine are genetically 

 connected with the other spore-forms on Peony, but also that they can 



