144 D- H. Scott. 



a structure comparable to that of tlie Corallinaceous genus Litho- 

 fhanmion. 



M. Zeiller says of the fossil Algae generally that they are not 

 separated by any prominent feature from tlie forms which we know 

 in the living state, and that it does not appear that plants of this 

 class have ever assumed characters very different from those met 

 with at the present day.^) However this maj^ be, it must be admitted 

 that existing palaeontological data do not materially add to our 

 systematic knowledge of the Algae. 



BACTERIA. The first evidence obtained for the existence of 

 Palaeozoic Bacteria was of an indirect nature. Van Tieghem in 

 1879 made the interesting observation that the cell-walls of silicified 

 vegetable tissues from the Coal-Measures of St. Etienne ai)peared to 

 show the effects of butyric fermentation, which is known to be due to 

 the action of Bacillus Amylohader; he further detected, as he believed, 

 the actual organism. Since that time much attention has been directed 

 to the subject of fossil Bacteria, especially by the late M. Renault, 

 and a number of supposed species have been described, chiefly of 

 Palaeozoic age. Although the value of such determinations, except 

 perhaps in the rare cases where the endospores have been observed, 

 is open to doubt, the existence of Bacteria in Palaeozoic times may 

 be taken as established. 



FUNGI. There can be no doubt that Fungi were abundant in 

 the Palaeozoic floras, although the evidence relates almost wholly to 

 microscopic members of the class. In examining the tissues of petrified 

 plants, mycelial liyphae are constantly met with, exactly as would 

 be the case with similar vegetable débris at the present day. Both 

 non-septate and septate liyphae occur, indicating that not only Ph}^- 

 comycetes but also the higher Fungi were represented. A characte- 

 ristic endophytic Fungus, probably referable to the Phycomycetes, 

 has been named Pcronosporites antiquarius, W. Smith. Its hyphae 

 bear definite, terminal or intercalary spherical vesicles, which may 

 have been of a reproductive nature. The common spinose bodies 

 known as Zygosporiies have been compared with the sporangia of 

 Mucor. Bodies resembling the perithecia of Sphaeriaceous Fungi have 

 often been observed on impressions of fossil plants. Recently Prof. 

 F. W. Oliver has described conceptacles containing spores, occurring 

 in the tissues of a silicified leaf of Aleihopteris. Prof. Magnus, the 

 distinguished mycologist, has pointed out the close agreement between 

 this organism and the Chytridineous Fungus Uroplilydis Kriegeriana, 



^) Éléments de Paléobotanique, p. 36. 



