CRYPTOGAMIA FUNGI. 207 



Hob. On the under surface of the leaves, and on the foot- 

 stalks of the valerians ( Vol. officincdis et dioica), not un- 

 common. 



15. y. Berberidis, spots collected into subcircular clusters with 

 a thickened red base ; cover cylindrical, elongate, with a circular 

 aperture ; disk orange. GREV. Crypt. Fl. t. 97 ; FL Edin. 446. 

 HOOK. Scot. ii. 14. 



Hob. On the leaves of the barberry, frequent. 



16. M. Tussilaginis, collected into round thickened clusters, the 

 spots arranged somewhat circularly ; cover whitish, short, with a 

 toothed aperture; disk reddish-orange HOOK. Scot. ii. 14. GREV. 

 Fl Edin. 447. 



Hob. On the under surface of leaves of colt's-foot, very 

 common, from spring to autumn. 



17. JB. Allii, spots arranged in concentric circles on a pale spot 

 of the leaf, not thickened, small, with a whitish circular toothed 

 aperture ; disk yellowish. GREV. Fl. Edin. 447. 



Hob. On both surfaces of the leaf of broad-leaved garlick 

 (A. ursinum). In the dean below Dulaw, Berwickshire. 



18. M. cornutum, clustered on an orange-coloured thickened 

 spot, the cover forming long, curved, cylindrical tubes of a pale 

 brown HOOK. Scot. ii. 14, GREV. Fl. Edin. 447; Crypt. Fl. 

 t. 180. 



Hob. On the under surface of the leaves of the roan-tree, 

 in autumn. Houndswood. 



This curious species is often imperfectly developed, nothing 

 appearing on the leaf but a thickened brown spot. 



19. M. laceratum, densely aggregated ; cover elongated, sub- 

 immersed, pale brown, irregularly torn GREV. Fl. Edin. 447. 

 Crypt. Fl t. 209. 



Hab. On the nerves and petiols of the leaf, and on the 

 fruit of the hawthorn, not common in this neighbour- 

 hood. My specimen is from Elmford, Berwickshire. 



The circumstances which determine the choice are unknown 

 but while some plants are annually much infested with 

 jEcidia, others are invariably exempted from their attacks. 



