STEVENSON. es 
Chemung and Catskill. 
1, CATSKILL. 2,500 
2. CHEMUNG. 
1. Haun’s Bridge group 1,000° 
2. Lackawaxen conglomerate 20" 
83. Sandstones and shales 1,000’ 
4, Allegrippus conglomerate 5! 
5. Shales and flags 3,250’ 4,675’ 
The Haun’s Bridge group consists largely of greenish gray 
sandy shales and flags with some red beds, and holds from bottom 
to top Chemung mollusks, some of which are very abundant. 
Prof. White’s measurements near Catawissa, in Columbia 
county, Pennsylvania, about sixty miles further along the strike, 
show the section still persistent, the suecession being :* 
J. CATSKILI, 3,280 
2. CHEMUNG. 
1. Shales and sandstones 923’ 
2. Lackawaven conglomerate 40’ 
3. Shales and sandstones 1,180’ 
4, Allegrippus conglomerate 10’ 
». Shales, sandstones and shaly 
beds 2,800' 4,453’ 
The Catskill exhibits little change in structure and, as before, 
appears to have no fossils aside from obscure fish remains. No. 
1 of the Chemung is the same with the Montrose shales of 
Susquehanna county as well as the Haun’s Bridge group of 
Huntingdon county. It consists, as it does further south, of 
variegated shales and sandstones, greenand red predominating, 
and in the lower half has many beds carrying Chemung mollusks. 
I have drawn the line between Chemung and Catskill somewhat 
arbitrarily, where sandstone ceases to predominate, for there is 
no noteworthy physical change in character of the rocks anywhere 
above the Lachkawaxren conglomerate. That conglomerate is now 
irregular in structure, sometimes not conglomerate, but still con- 
taining fish-bones as it does further south. The fragments of 
bones are larger and in better preservation than at the more 
southern localities. 
The interval between the conglomerates contain some red beds 
but as usual they form only a small part of the section, little 
more than ten per cent of the whole. A bed containing frag- 
ments belonging, apparently, to //oloptychius associated with 
Pleurotomaria sp. and Lingula spatulata, was observed at 150 
feet below the Lachawaxen conglomerate. Vegetable remains 
*The Geology of the Susquehanna river region, I. C. White, Harris- 
burg, 1883, p. 57. 
