202 



44. — Pcsiza Bidlii, Smith. Bull's Peziza. On water butt. 

 45. — Orbicula cyclospora, Cooke. Paper Orbicula. On varnished wall 

 paper. 



4t). — Orbicula pcrichoenoidcs, Cooke. On beams in old houses. 



ON THE IMPORTANCE THAT SHOULD BE ATTACHED 

 TO THE DEHISCENCE OF ASCI IN THE CLASSI- 

 FICATION OF THE DISCOMYCETES. 

 [By Monsieur E. Boudier— Translated by W. Puillip.s, F.L.S.] 



The discovery of the mode of dehiscence of the Asci in the Discomycetes is of 

 recent date. Leveilld in the article Peziza in the Dictionnaire d'Histoire Natu- 

 relle de D'Orbigny, confessed he had never seen it, and it is to M. M. Crouan that 

 we owe the first observations on the subject. These gentlemen saw clearly the 

 operculum in the Ascoboli, and in some neighbouring species, but said they had 

 never met with it in any other Pezizee. They also made it the special character 

 of Ascobolus, and joined some species of the neighbouring genera amongst which 

 they had observed it. More recently, in their " Florule du Finistere, " in 1867, 

 they imperfectly saw another mode of dehiscence in Lccanidium atrum (^Patel- 

 laria atrata Fr.), but they described it badly, for the sporidia, in all the Pezizse, 

 are discharged at the same time. The observations of these scientific men rested 

 here, and they did not attach sufficient importance to their discovery. 



Since this period, in 1869, in my "Memoir sur les Ascoboles," I have 

 pointed out the fact that this group was not the only one in which the asci may be 

 provided with an operculum, and that this mode of dehiscence was to be met with 

 in Pezizae of the sections Humaria, Sarcoscypha, Aleuria, and likewise in Vcrpa, 

 Hclvclla, and Morchella, while Hdotium and the neighbouring genera Lcotia, 

 Mitrula, and Geoylossum presented a different mode of dehiscence. 



At this time, after the examination of a considerable number of Discomy- 

 cetes, I am able to call the attention of mycologists to the necessity of separating 

 this family into two very natural sections, according as to whether the mode of 

 dehiscence is with, or without an operculum. I would call the first section by the 

 name of Operculate Discomycetes, or simply Opercida, because in this section the 

 opening of the asci takes place by the elevation of a little lid at its summit. The 

 second I would call Inopcrculatc Discomycetes, or simply Jnoperculce, because the 

 exit of the sporidia takes place by a small hole, formed at the extreme summit of 

 the asci, with itsjmargin more or less elevated, but without any appearance of an 

 operculum. 



There is no great diflBculty in observing this dehiscence, although few authors 

 mention it. A very little attention soon renders it quite familiar, and I consider 

 its careful observation indispensable to a good classification of genera and species. 



