380 CJREDINOPSIS 



pedicels as long as <.r longer than the spore, colourless, densely 

 verruculose, averaging 20 — 2(j x 12— 14/z: epispore about 1 fi 

 thick: (2) larger, aboul j mm. diam., more elevated, pustular, 

 withoul (?)peridium, but with what looked like hyaline clavate 

 i hiii-wallcd paraphyses; spores ovate-fusiform, colourless, smooth, 

 thickened at the apex with a conical, acute, usually oblique 

 process, 35 — 45 x 10 — 12 /u, : pedicels short; epispore thin. 



Teleutospores. Scattered singly throughout the mesophyll. 

 Le. >i«>t in definite clusters, roundish-oval or oblong, 1 — 3 

 (mostly two) celled, 18 — 24x15 — 16//; epispore very thin, 

 almost perfectly hyaline and smooth. 



On Polypodia in Phegopteris. Europe. Not uncommon; 

 appearing about the time when the fern-sori are being formed. 

 The uredo-sori are of about the same size as a fern-sporangium, 

 and are scattered among the fern-sori. (Fig. 284. ) 



The description and figures are taken from a German specimen. The 

 fungus will no doubt be found in this country, if looked for ; it is rather 

 conspicuous on account of the uredo-sori. The warts on the uredospores 

 (no. 1) are clearly perceptible even when wet : the peridium is pseudoparen- 

 chymatous, with cells isodiametric near the apex, becoming longer and 

 prosenchymatous towards the periphery; texture rather tough and con- 

 sistent, not friable. Fischer gives a beautiful and accurate drawing of the 

 nature of the peridium and its relation to the epidermis (I.e. fig. 310). 



The uredospores (no. 2) are described by Arthur in his generic character 

 (N. Amer. Flora, vii. 115) as smooth, except for two longitudinal, thickened, 

 more or less warted ridges, which I could not discern. 



As in Hyalopsora, Arthur prefers to call the two kinds of uredospores 

 respectively secidio- and uredo-spores : the same remark may be made as 

 under that genus, for the supposed secidiospores occur in company with 

 the teleutospores on the dying parts of the frond, and are said to germinate 

 only after having passed the winter. Uredospores (no. 2) can germinate 

 at once. 



The teleutospores are to be found in large numbers in the tissues 

 immediately round both kinds of sori, and simultaneously with them. 

 They are borne on short lateral branches of the mycelium. Dietel, who 

 o-ave a long account of this fungus (Ber. Deutsch. Bot. Gesell. 1895, xiii. 

 326 . showed that in the allied European species, U. Struthiopteridis, the 

 teleutospores germinated easily with a typical basidium (occasionally 

 branched) which bore round basidiospores. 



Distribution: Germany, Switzerland, Italy. 



