PHACIDIUM. 



387 



Order VIII.— PHACIDIACEiE. 



Receptacle immersed, more or less coriaceous ; hyme- 

 nium at first covered, at length exposed by the regular 

 or irregular fissure of the outer covering. (Plate XII. 

 figs. 76-78.) 



Name — From the typical genus Phacidium. 



Arrangement op the Genera. 



I. Phacidium. Fries. 

 II. Trochila. Fries. 



III. Stegia. Fries. 



Key to the Genera. 



Hymenium becoming exposed by the epidermis of 

 the matrix splitting from the centre into laciuise 



Hymenium becoming exposed by splitting at the 

 summit irregularly 



Hymenium becoming exposed by the falling off of 

 a horizontal operculum 



Phacidium. 



Trochila. 



Stegia. 



Genus I. — Phacidium. Fries. 



Perithecium orbicular, flattened, subdimidiate, de- 

 hiscing from the centre into lacinise, distinct from the 

 placentiform disc. (Plate XII. fig. 76.) 



The perithecium is covered by the epidermis of the 

 matrix; the hymenium is mostly dark-coloured, lining 

 the base of the perithecium. 



On leaves and bark. 



Name — (paKog, a lentil, £$og, resemblance ; shaped 

 like a lentil. 



Arrangement of the Species. 



B. 

 C. 



Sporidia elliptic or subelliptic. 



(a) Brown 



(b) Hyaline 



Sporidia fusiform or subfusiform 

 Sporidia filiform or subfiliform 



Key to the Species 



On trees and shrubs . 

 On herbaceous plants . 

 , (On the stems . . 

 \On the leaves . . 



species 1 



n 2-6 



„ 7-10 

 11-16 



»> 



1 

 4 

 2 

 3 



