184 British Fttngi. 



or irregularly subrotund, rarely broadly elliptical, 

 25-28 or 24-26 x 27-30 /x; epispore clear dark 

 brown, with thin ridges 2*5-3 yu, high, combined to 

 form a network having meshes about 4 /^ diameter ; 

 germination not known. 



TiUetia decipiens, Korn. in Winter, Pilze, p. Ill ; 

 Plow. Brit. Ured. and Ustilag. p. 284 ; Sacc. Syll. 

 vii. i. n. 1762. 



In the ovary and glumes of Ar/rostis vulgaris, 

 Agrostis alba, and Apera spica-venti. When AgrosUs 

 vulgaris is attacked the plants are dwarfed, and were 

 considered as a distinct species by Linnseus under the 

 name of Agrostis pumila ; by others the dwarfed 

 form is reckoned as a variety of A. vulgaris, but 

 it was long since shown to be only al. vulgaris. Not 

 uncommon. 



B. Epispore covered until spines. 

 TiUetia striiformis, Magnus (figs. 83, 84). 



Sori forming long, parallel, brownish-black streaks, 

 minutely pruinose, becoming pulverulent ; resting- 

 spores globose, broadly elliptical, or irregular globose, 

 olive-brown, epispore covered with slender spines 

 about 1 fjL long, connected at the base by a delicate 

 reticulation, 10-13, or 11-16 x 8-11 p, ; primary 

 sporidia linear, elongated, often conjugating in pairs. 



TiUetia striiformis, Magnus, in Winter,-- Pilze, p. 

 108 ; Plow. Brit. Ured. and Ustilag. p. 284 ; Sacc. 

 Syll. vii. i. n. 1 774. 



On the leaves, leaf-sheaths, and stems of various 

 grasses belonging to the following genera, Alopecurus, 

 Avena, Milium, Holcus, Anthoxantlium, Briza, Poa, 



