130 NEW YORK STATE MUSEUM 



Chapter 4 

 FOSSILS OF THE NIAGARA REGIONi 



PLANTS 



The Paleozoic marine plants or seaweeds are generally classed 

 together as " fucoids ", a term denoting a relation of these organisms 

 to the modern rockweed, F u c u s , which fringes the rocks of our 

 seacoast. These plants were probably algae, but it is impossible in 

 most cases to make a more precise classification. The condition in 

 which these remains are found today — as a rule mere impressions or 

 casts of the original — generally renders the determination of their 

 afBnities a hopeless task. In some remains the plant nature of the 

 organism is even questionable. 



Genus bythqtrephis Hall 

 [Ety. : i3odoTp£<p7j?, growing in the deep] 



(1847. P(^l- ^' y- 1:8) 

 Plant consisting of subcylindric or compressed stems, usually flat- 

 tened on the rock surfaces and having numerous spreading branches, 

 which in some species are leaf-like. 



Bythotrephis gracilis Hall (Fig. 25) (1852. Pal. N. Y 2:18, 



pi. 5) 



Distinguishing characters. Slender branches diverging at varying 

 angles from a central stipe which not infrequently bifurcates. Ter- 

 minations of branches round to pointed. 



^In this chapter only the Siluric fossils of the Niagara region will be 

 considered, those of the Devonic limestones, which border this region on 

 the south being so numerous that they must be reserved for a future pub- 

 lication. No attempt is made to add to the number of known species of 

 Siluric fossils of the Niagara region. Of described species those only 

 which have been found in this region or recorded in the literature 

 as coming from it have been included, with the addition of such species 

 froni neighboring localities as occur there abundantly, and may reasonably 

 be expected to occur in the Niagara sections. An exhaustive study of the 

 Niagara fauna of western New York has still to be made. In chapter 5 

 a complete account of all the post-Pliocene shells so far found in the 

 Niagara gravels is given, this being the first time that these shells are 

 described and illustrated. 



