234 DESCBIPTITE CATALOGUE 



Among living Algae the majority of the larger forms are 

 marine and the group preponderates largely in the sea-water 

 flora as a whole. It is, therefore, all the more surprising that so 

 few good fossil examples are recorded. That Algae existed from 

 Palteozoic times is rendered certain by the fact that one of the 

 earliest known plants with its internal structure preserved is 

 an alga, Nematojjhycus (Dawson), Garruthers. The theory that 

 all terrestrial vegetation originated from aquatic forms in the 

 earliest times, is also generally accepted. The mere delicacy of 

 the tissues forming the Algae is not a sufficient explanation for 

 the remarkable poverty of their petrifaction, for equally delicate 

 parts of the higher plants are preserved ; and it is probably 

 due to the chemical nature of their cell-walls that they are so 

 ill represented in fossil floras. 



Although large numbers of appearances in the rocks have been 

 described which are not Algae but are of purely physical origin, 

 many writers have hastily discarded specimens which merit re- 

 tention because of the unsatisfactory nature of most fossil Algae. 

 Seward (1894) has discarded all the numerous generic names 

 given to algal impressions and proposed the comprehensive 

 generic name Algites for everything. For the Cretaceous plants 

 this course does not" seem advisable, because a number of the 

 described species are at least as good as many of the fossil fern- 

 species which are retained by all palaeobotanists, while at the 

 same time it is recognised that their affinities are very imperfectly 

 known. 



The literature dealing with fossil Algae is extensive, and much 

 of it is highly controversial. In a Swedish paper in 1874 

 N athorst showed how many of the fossil " algae '' were simply 

 physical markings, and he continued his work in 1881. To this 

 Saporta replied in 1882 with a large monograph on the fossil 

 Algae. Nathorat published a more exhaustive paper in 1886 in 

 reply both to Saporta and the others who continued to maintain 

 the algal nature of the remains. In 1895 fuchs contributed a 

 large paper on " Fucoiden und Hieroglypheu", and stated that 

 after an exhaustive examination of all the " fucoids" in most 

 museums, he did not discover a single carbonised specimen, and 

 he denied the statements made by other workers that such spe- 

 cimens are frequent. His opinion was that all the so-called 



