1915] 



ATKINSON PHYLOGENY IN THE ASCOMYCETES 



359 



ii leaved families and show very plainly the morpholog- 

 characters of their antecedents. But he says it is quite 



, The simplest primitive forms of 



otherwise with the fung 

 the Ascomvcetes, 



Phycomycetes and Basidiom 



have 



given rise independently to an enormously high state of dif 



fe 



Now Sachs in 1896 (and 



74 



310) 



recognized Gymnoascus as belonging to the simplest A 



pollinode. 

 the Ascom 



o ___ f which are a simple carpogone and 



It is very clear then that Sachs would not derive 

 fcetes from any primitive form at all like any 



known red algae, much less through such forms as the highly 

 pecialized Collema or Polystigm 



This 



eluding that Sachs had in mind a primitive hypothetical an- 

 cestor of the sac fungi and red algae, which possessed simple 

 copulating gametes. With the knowledge we possess to-day 

 of such forms as Dipodascus, Eremascus, etc., where the 

 zygote becomes the ascus (generalized or simple) I believe he 

 would have recognized in the Phycomycetes, as we know them 

 to-day, a situation very closely approximating an "Urform" 

 for the Ascomvcetes, particularly in view of the fundamental 



difference in the 



of the red algae and sac fungi 



But whether the fungi represent one or several architypes 

 it by no means follows that, because of the absence of chloro- 

 phyll, they must be derived from green plants, or that each 

 great series must be derived separately from different groups 



of 



The appearance of the higher fungi (Eumycetes) was, in 

 the opinion of Vuillemin ('12, p. 223), contemporaneous with 

 the emergence of sea-shore, which abandoned certain red algae 



terrestrial life. This new environment introduced the 



to 



change, which, accompanied by loss of chlorophyll 

 first to the Pyrenomycetes, from which the other higher fungi 



The sapro- 



Uredinal 



Basidiomi 



have 



ginated 



phytic forms represent the productive and progressive stock 

 Parasitic groups, like the Uredinales, Laboulbeniales, lichens 

 etc., are composed of highly specialized and uniform members 

 their progressive potentialities being suppressed, but they re 

 tain their hold on existence because of their specialized hab 



