Enough has been said to call attention to the paucity of exact data on which to generalise as to the geological history 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, _Palaeomyces_, might be employed as a useful and comprehensive designation. VII. CHAROPHYTA. CHARACEÆ. NITELLEÆ. It has been the general custom to include the Characeæ or Stoneworts among the Chlorophyceae (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[437] and allow the Characeæ 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. The Charophyta are plants containing chlorophyll, living in fresh and brackish water; the stem is jointed, and bears at the nodes whorls of leaves, on which are borne the reproductive organs. The antheridia are spherical in shape and of complex structure, containing numerous biciliate antherozoids. The oogonia are oval in form and contain a single large egg-cell. The Chara-plant is developed from a _protonema_ formed from the germinating oospore. Vegetative reproduction is effected by means of bulbils, accessory shoots, etc. The Nitelleæ have not been recognised in a fossil condition. The absence or feeble development of a calcareous incrustation renders the genera of this family less likely to be preserved than such a genus as _Chara_. Chareae. Leaves and stems with or without a cortical investment. Fruit with a five-celled _corona_. The envelope of the ‘fruit’ and other parts of the plant are frequently encrusted with carbonate of lime.