THE ERIAN OR DEVONIAN FORESTS. 



57 



dant are those spinous and hooked spores or sporangia, 

 to which the names Sporocarpon, Zygosporites, and Tra- 

 quaria have been given, and some of which Williamson 

 has shown to be spores of Lycopodiaceous plants.* 



The true " Sporangites," on the contrary, are round 

 and smooth, with thick bituminous walls, which are 

 punctured with minute transverse pores. In these re- 

 spects, as already stated, they closely resemble the bodies 

 found in the Australian white coal and Tasmanite. The 

 precise geological age of this last material is not known 

 with certainty, but it is believed to be Palaeozoic. 



With reference to the mode of occurrence of these 

 bodies, we may note first their great abundance and wide 

 distribution. The horizontal range of the bed at Kettle 

 Point is not certainly known, but it is merely a northern 

 outlier of the great belt of Erian shales referred to by 

 Prof. Orton, and which extends, with a breadth of ten to 

 twenty miles, and of great thickness, across the State of 

 Ohio, for nearly two hundred miles. This Ohio black 

 shale, which lies at the top of the Erian or the base of 

 the Carboniferous, though probably mainly of Erian age, 

 appears to abound throughout in these organisms, and in 

 some beds to be replete with them. In like manner, in 

 Brazil, according to Mr. Derby, these organisms are dis- 

 tributed over a wide area and throughout a great thick- 

 ness of shale holding Spiropliyton, and apparently belong- 

 ing to the Upper Erian. The recurrence of similar forms 

 in the Tasmanite and white coal of Tasmania and Aus- 

 tralia is another important fact of distribution. To this 



* Tr aquaria is to be distinguished from the calcareous bodies found 

 in the corniferous limestone of Kelly's Island, which I have described in 

 the " Canadian Naturalist " as Saccamina Eriana, and believe to be Fo- 

 raminiferal tests. They have since been described by Ulrich under a 

 different name (Moellerina : contribution to " American Palaeontology," 

 1886). See Dr. Williamson's papers in " Transactions of Koyal Society 

 of London." 



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