270 INTRODUCTION TO THE STUDY OF FUNGI 



Godroniella, a genus in which the receptacle is composed of 

 agglutinated hyphae, in other respects scarcely differing from 

 the next genus, Excipula, in which the excipulum is cellular, 

 membranaceous, or tough, and black. The genus Excipula of 

 Fries, and many subsequent authors, was rather a heterogeneous 

 one, even including some ascigerous species, and the residue 

 are now distributed over six different genera. Heteropatella 

 differs in the perithecia being thicker and more leathery, with 

 the mouth always contracted and torn, the sporules fusiform, 

 growing upon branched sporophores. In Dothichiza the black 

 receptacles are mostly erumpent, often gregarious, at first closed, 

 then rather cup-shaped, and are often the spermogonia of species 

 of Cenangium. Sporules oblong and continuous. In Zemalis 

 the receptacles are membranaceous, or rather fleshy, coloured, 

 but not black. Gatinula has the receptacles tough or horny, 

 and black, rather cup -shaped, disc often bright coloured. 

 Discula corresponds to Discella, but the sporules are continuous. 

 The receptacles are discoid or patellate, often imperfect, black or 

 coloured. Hereafter follow the genera in which the perithecia 

 are hysteriform or valvate. In Sporonerna the receptacles are 

 valvate, dehiscing with angular teeth, as in Phacidium, of 

 which they are possibly a stylosporous condition. Pleococcum 

 is scarcely distinct from Sporonerna, although the contents are 

 assumed to be more mucilaginous. Psilospora closely resembles 

 Dichaena, of which it is evidently a stylosporous state. The 

 perithecia dehisce in the manner of Hysterium, with two 

 lips, and occur upon living bark of trees. The remaining 

 genera of the Hyalosporae possess hairy perithecia. The genus 

 Amerosporium has the receptacles cup-shaped, and corresponds 

 to Excipula ; but the cups are setulose, the sporules are naked 

 at the ends. In Dinemasporium the habit and external appear- 

 ance are the same, but the sporules have a hyaline bristle, or 

 awn, at each end (Fig. 124). Polynema differs in having the 

 apex of the sporules crowned with about four awns. In 

 the next section, the Hyalodidymae, there are but two genera. 

 In Discella the perithecia are normally discoid, sometimes 

 imperfect, or formed from the matrix, a long time covered by 

 the cuticle. Sporules oblong, uniseptate, and hyaline. In 

 Pseudopatella the receptacle is cup-shaped, almost superficial 



