222 THALLOPHYTA. [CH. 



of fungi. The types selected for description or passing allusion 

 have not been chosen in each case because of their special 

 intrinsic value, but rather as convenient examples by which to 

 illustrate authentic records or to serve as warnings against 

 possible sources of error. 



It would seem that we have fairly good and conclusive 

 evidence of the existence in Permo-Carboniferous times of 

 Phycomycetous fungi, but it is not until we pass to post- 

 Palaeozoic or even Tertiary plants that we discover satisfactory 

 representatives of the higher fungi or Mycomycetes. If special 

 attention were paid to the investigation of fossil fungi, it is 

 quite possible that our knowledge of the past history of the 

 group might be considerably extended. It is essential that 

 the greatest caution should be exercised in the identification 

 of forms and in their reference to definite families; otherwise 

 our lists of fossil species will serve to mislead, and to emphasize 

 the untrustworthy character of palaeobotanical data. Unless 

 we feel satisfied as to the position of a fossil fungus it is unwise 

 to use a generic term suggestive of a definite family or recent 

 genus. Such a name as Renault has used in one instance, 

 PalaeomyceSy might be employed as a useful and comprehensive 

 -designation. 



VII. CHAROPHYTA. 



CHARACEiE. NITELLE^. 



It has been the general custom to include the Characese 

 or Stoneworts among the Chlorophycese (green algae), of which 

 they form a distinctly isolated family. On the whole, it would 

 seem better to follow the course lately adopted by Migula^ and 

 allow the Characese to rank as a family of a distinct group, 

 Charophyta. While agreeing in many respects with plants 

 higher in the scale than Thallophytes, the Stoneworts do not 

 sufficiently resemble the Bryophyta to be included in that 

 group. 



1 Migula (90) in Eabenhorst's Kryptogavien Flora, vol. v. 



