9 6 



DISCOMYCETES 



[ch. 



the sides and bottom of the cup. In many cases, as in Pecisa vesiculosa and 

 Otidca aurantia, the cup is small and comparatively full when it first opens, 

 and grows larger and deeper as development proceeds. 



Fig. 53. Hiimaria rutilans (Kr.) Sacc. ; hymenial layer 

 showing asci and paraphyses in various stages of develop- 

 ment, x 400. 



Fig. 54. Mitrula laricina Mass*; 



development and ejection of 

 biseriate spores, x 600. 



This typically discomycetous ascocarp or'apothecium, which is well seen 

 in the Pezizales, may be connected in one direction, through the Patel- 

 lariaceae and their allies, with the fructifications of the Phacidiales, which are 

 parti}- closed with a more or less stellate aperture, and with the characteristic- 

 ally elongated fructifications of the Hysteriales, which open by a narrow 

 slit. The apothecia of this last series show a close resemblance to the 

 perithecia of certain Pyrenomycetes, and, as far as their mature structure 

 is concerned, they may be placed as logically in one group as the other. 

 Nor have we at present any information with regard to development which 

 can decide the question. It remains even possible that the Hysteriales are 

 a transition series and that some of the forms grouped among Discomycetes 

 may have arisen from the Pyrenomycetes or vice versa. 



In another direction the typical apothecium, when very widely open ; 

 suggests the reflexed ascocarp of Rhiziua or Sphaerosoma and such a type 



