MONOGRAPH OF THE LABOULBENIACEiE. 



255 



remote relationship to the Hypocreaceoe, it is worthy of note that the bodies most 

 nearly resembling the characteristic antheridial cells found in the family are the 

 " Hyphopodics mucronees" of the Meliola) ; but having as yet been unable to ex- 

 amine the latter in a fresh condition, I can at present merely suggest the possibility 

 of a similarity of function. 



In arranging the genera under which are grouped the species included in the fol- 

 lowing systematic enumeration, the primary divisions have been based on the 

 characters of the male sexual organs. Forms having antherozoids exogenously pro- 

 duced, have been separated in a group of " exogenae," comprising but two genera, 

 while the remaining twenty-six genera having antherozoids that are produced endo- 

 genously, are placed in a second group of " endogenae." 



The two genera of the first-mentioned group are both primarily aquatic, and if we 

 entertain the suggestion that the family has been derived from carposporic algal 

 ancestors, might, from their simple antheridial branches and their aquatic habit, be 

 considered as probably the more primitive of the two groups. Of this group, the 

 genus Ceratomyces may be taken as the type, since it illustrates most clearly not only 

 the exogenous formation of antherozoids, but the indeterminate development of the 

 perithecia and their tendency towards an appendiculate condition. 



The twenty-four genera of the second group offer many difficulties, if one attempts 

 to arrange them in lineal sequence ; but here again the character of the male sexual 

 organs affords a natural means for their general separation into two groups, charac- 

 terized in the one case by the presence of what have been previously described as 

 " compound," in the other of " simple " antheridia, and these again may be sub- 

 divided according as the sexual organs occur on the same or on different individuals. 



A further subdivision has been employed in the following synopsis based upon the 

 determinate or indeterminate arrangement of the antheridial cells ; but this dispo- 

 sition, while it expresses, in a measure, true relationships, by bringing together such 

 genera as Idiomyces, Stigmatomyces, and Helminthophana, is not wholly satisfactory. 

 Further than this, a definite arrangement into not too numerous sub-groups is hardly 

 possible, although it is evident that genera like Moschomyces, Compsomyces, and per- 

 haps Sphaleromyces, or Teratomyces and Diplomyces should go together. A more 

 definite appreciation of their further relationships will no doubt become possible after 

 the discovery of additional genera ; but at present it would be quite superfluous to 

 attempt to represent them graphically. 



