2 



Mycologia 



two species on both plates. If Rehm is correct in placing the 

 two species in the same genus, there is no longer any reason for 

 considering them specifically distinct since Fries used the same 

 character in segregating the genus as had previously been used 

 by Schaeffer in separating the species. Gyromitra can not then 

 be regarded as a valid genus, since it was founded on a supposed 

 difference which has been found to no longer exist. 



Boudier retains the genus Gyromitra, but bases it on an en- 

 tirely different character so as to exclude from the genus the 

 very species on which it was founded. A new genus Physomitra 

 is then proposed which includes the two species which he calls 

 Physomitra infula and Physomitra esculenta. In his description 

 of the last two species, there is a slight difference in the size of 

 the spores, a difference, however, which had not been noted by 

 previous authors. 



While, to be sure, other differences have been pointed out by 

 more recent authors in addition to those originally mentioned by 

 Schaeffer and Fries, such as the shape of the pileus, the color, 

 the attachment of the pileus to the stem, the inflation of the cap, 

 etc., none of these characters appear to the writer to be any more 

 fixed and reliable than the one originally mentioned. The type 

 of the genus Elvela has the pileus more or less adnate to the 

 stem, so that this character cannot be used as a distinguishing 

 character between' Elvela and Gyromitra. Even the original 

 illustration of the type of the genus Gyromitra does not show the 

 pileus completely attached to the stem at the margin, as might 

 be inferred from many modern illustrations and descriptions. 

 The inflation of the cap is a character which is common to both 

 Elvela infula and Gyromitra esculenta and one which is most 

 variable and misleading. 



The difference in the rugosity or gyrosity of the hymenium 

 might be accepted as a good specific and possibly generic char- 

 acter were it not for the fact that we often find all stages of 

 gyrosity in specimens growing apparently from the same myce- 

 lium, and which we have no reason to believe do not represent 

 the same species. It seems to the writer that it was a mistake to 

 establish a genus on a character which is of very doubtful specific 



