APPENDIX. Xii 



shining coaly covering polished and striated by the slipping of 

 contiguous portions of the matrix under great pressure. 



Owing to the fact that nearly or quite all of the plants I 

 obtained here in a condition to show their specific characters 

 seem to be new species, while no other organic remains of any 

 kind were observed in these beds during my rather limited ex- 

 amination, we scarcely have the means of determining their exact 

 horizon in the series. The aflSnities of the several species of 

 ferns found in the bed at the bottom of the cut, at this place, 

 would, however, favor the conclusion that they belong near the 

 junction of the Old Red Sandstone and the lower Carboniferous, 

 but probably in the latter. 



That the remains of Chemung types of shells occur at lower 

 stratigraphical positions at several places between -here and Al- 

 leghany tunnel, has already been stated. There must, however, 

 be a considerable thickness of strata intervening between these 

 two points, the dip being all along here, I should think, scarcely 

 less than 30° to 40° below the horizon, and perhaps at some 

 points more, to the southeastward. I made no measurements 

 of distances, angles of dip, or of the thickness of strata (having 

 no instruments), but the distance between the two tunnels, by the 

 curve of the road, is, I was informed, about one and a half miles. 

 A straight line between these two points, however, would not be 

 in the direction of the dip, but obliquely across the strike, and 

 something less. 



The distance, by a right line, between the locality where I 

 found the last Chemung fossils, coming eastward, and the point 

 where the remains of the plants were found in the cut at Lewis' 

 tunnel, 1 should think little more than half a mile ; and, making 

 allowance for the direction of this line with relation to the dip, 

 there would seem to be scarcely less than 1500 feet of strata, and 

 possibly more, between the horizons of these two points. How 

 much if any of this space may be occupied by Chemung rocks 

 remains to be determined. That the Chemung extends from the 

 furthest eastward point at which I found its characteristic fossils, 

 back to Alleghany tunnel, however, where the same types occur, 

 there can be no doubt, and there appears to be good reason to 

 believe that there are from 1200 to 1.500 feet of these rocks be- 

 tween these two points. Whether or not the Chemung extends 

 back into Alleghany tunnel, I did not ascertain. I think it pro- 

 bable, however, that at least a part of the strata penetrated by 

 this tunnel belongs to the horizon of the Portage group, because 

 among the material brought out of its eastern end, I saw many 

 thin slabs, of bluish and greenish tinge, showing, on their slightly 

 glazed surfaces, fucoidal markings very similar to Fucoides 

 graphica, so characteristic of the Portage group in New York. 

 There is ample space between this point and the White Sulphur 



(37; 



