THE BRIAN OR DEVONIAN FORESTS. 



51 



1882, when Prof. Orton, of Columbus, Ohio, sent me 

 some specimens from the Erian shales of that State, 

 which on comparison seemed undistinguishable from 

 Sporangites Huronensis.* Prof. Orton read an interest- 

 ing paper on these bodies, at the meeting of the American 

 Association in Montreal, in which were some new and 

 striking facts. One of these was the occurrence of such 

 bodies throughout the black shales of Ohio, extending 

 "from the Huron Kiver, on the shore of Lake Brie, to 

 the mouth of the Scioto, in the Ohio Valley, with an 

 extent varying from ten to twenty miles in breadth," and 

 estimated to be three hundred and fifty feet in thickness. 

 I have since been informed by my friend Mr. Thomas, of 

 Chicago, that its thickness, in some places at least, must 

 be three times that amount. About the same time. Prof. 

 Williams, of Cornell, and Prof. Clarke, of Northampton, 

 announced similar discoveries in the State of New York, 

 so that it would appear that beds of vast area and of great 

 thickness are replete with these little vegetable discs, usu- 

 ally converted into a highly bituminous, amber-like sub- 

 stance, giving a more or less inflammable character to the 

 containing rock. 



Another fact insisted on by Prof. Orton was the ab- 

 sence of Lepidodendroid cones, and the occurrence of 

 filamentous vegetable matter, to which the Sporangites 

 seemed to be in some cases attached in groups. Prof. 

 Orton also noticed the absence of the trigonal form, which 

 belongs to the spores of many Lepidodendra, though this 

 is not a constant character. In the discussion on Prof. 

 Orton's paper, I admitted that the facts detailed by him 

 shook my previous belief of the lycopodiaceous character 



* These shales have been described, as to their chemical and geological 

 relations, by Dr. T. Sterry Hunt, "American Journal of Science," 1863, 

 and by Dr. Newberry, in the " Reports of the Geological Survey of Ohio," 

 vol. i., 1863, and vol. iii., 1878. 



