PHYLOGl \) AND CL KSSIl IC IT/ON // 



we prefer the conservative point <>! view expressed l>\ the use oi by- 

 phal arrangement in the hymenophore at the sectional level. 



Assuming that species of CamarophyUopsis are primitive and re- 

 semble species of ConthoreUus more closel) than those of the various 

 sections of Hygrophorus, we must accept the Fact that gymnocarpic de 

 velopment is a more primitive condition in the Hygrophoraceae than 

 the hemiangiocarp) displayed by a number of species in section ////- 

 grophorus. This certainly "fits" the circumstances since CanthareUus is 

 characterized by gymnocarpic development <>1 the Fruiting body. This 

 line of reasoning would point to //. olivaceoalbus .is perhaps the most 

 advanced species in the section Hygrophorus — at least as t tr as those 

 we have studied are concerned. As to the section Hygrocybe, the most 

 specialized group would appear to be those with both a viscid stipe 

 and pileus, subsection Psittacini. The members oi secti< n Hygrotrama 

 appear to have been derived from the area of Camarophyllopsis near- 

 est the series Hygrocyhe of section Hygrocybe I the //. miniatus 

 group). Our basis for this conclusion is that it is in this area that 

 the epicutis of the pileus shows transitions from appressed fibrils to a 

 true trichodermium, and by a shortening of the triehodermial hyphae 

 the hymeniform type of epicutis is readily derived. As for certain other 

 characters in the genus, the nodulose spores could have arisen de novo 

 anywhere in the genus. This character has thus appeared in a number 

 of groups of Hymcnomijcetes. The amyloid spores of a tew specii 

 character taken by itself, can just as readily be interpreted on the same 

 basis as the nodulose character of the spores. For this reason we do not 

 place Pseudohygrophorus in the direct line from CanthareUus; to Cam- 

 arophyllopsis, and we recognize the section Amylohygrocybe larger) 

 as a taxonomic convenience. Bertrandia Heim appears to us, from ac- 

 counts in the literature, to be amply distinct as a genus. We have exam- 

 ined no material and have nothing to offer as to its possible derivation. 



Although our ideas of the evolution of the Hygrophori have been 

 discussed onlv in the light of our owti data on North American species, 

 a survey of the literature, although not very enlightening, shows that 

 approximately the same ideas have been expressed or implied b\ 

 other investigators. Kiihner and Romagnesi ( 1953 I arrange Hygropho- 

 rus following CanthareUus, which is exactly the 1 position we would as- 

 sign to it, except that these 4 authors treat Hygrocybe first (as a genus), 

 Camarophyllus next, and Limacium last. Singer I 1951) armies for the 

 recognition of Hygrophorus (Limacium), Camarophyllus, and Hygro- 

 cybe as genera; but since the family Hygrophoraceoi is the first group 

 treated in his work it is not clear from what source he thought it 

 derived. He said, "Hardly anything can be said about the origin of 



