344 BRITISH DISCOMYCETES. 



Name — Rhabarbarum, another name for Rheum, the 

 genus to which rhubarb belongs. 



King's Lynn ! (Mr. C. B. Plowright). Hencott, neai 

 Shrewsbury ! 



9. Dermatea Fagi (nov. sp.). 



Erumpent, the orbicular or elliptic groups 1 to 8 lines 

 across, splitting the epidermis ; cups plane or slightly 

 convex, mostly immarginate, when moist orange-yellow, 

 when dry ferruginous-yellow, pruinose, densely crowded 

 on an evident stroma; stem when present stout, con- 

 tinuous with the stroma ; asci broadly clavate ; sporidia 

 8, elliptic or oblong-elliptic, filled with coarsely grained 

 protoplasm, sometimes becoming muriform, 18 — 23 x 9 — 

 12/*; paraphyses slenderly filiform, abundant. 



Stylospores oblong-elliptic or elliptic, 10 — 20 x 7 — 9/*; 

 produced on the surface of the stroma in tufts between 

 the cups on clavate sporophores. 



On Fagus sylvatica. 



The cups are \ to J a line broad. The coniclia are 

 produced in such a quantity as to form a pale stratum 

 visible under a pocket lens. I am not aware that they 

 have been observed in any other species. 



Name — From the tree on which it grows. 



Kingcausie, near Aberdeen ! 1880. 



Genus III. — Cenangium. Fries. 



Receptacle closely shut, at length more or less open, 

 raarginate, with a thick epidermis of a different colour ; 

 hymenium even, persistent ; asci cylindraceo-clavate ; 

 sporidia 8, elliptic, oblong, fusiform or filiform. 



Pycnidia immersed, conical, unilocular ; stylospores 

 ovate or slenderly fusiform. (Plate X. fig. 66.) 



The receptacles are erumpent, sessile or subsessile ; 

 their exterior coriaceous or membranaceous, the interior 

 somewhat grumous. Pycnidia have not been observed 

 in all. 



