Notes on the Geology of Yates County, N. Y. 205 



After leaving this point on the route to Seneca lake through Kash- 

 ong creek, we first descend through fifty-five feet of nearly horizontal 

 shale, occasionally interrupted by layers of sandstone. In this, and 

 about two- thirds the distance down, we found the spine of a new species 

 of Ctenacanthus, the description of which, by Dr. J. S. Newberry, is 

 herewith published for the first time. [See end of this paper.] This 

 stratum terminates in a bed of pyritiferous shales. This is followed by 

 eight feet of coarse shales, which are remarkably rich in Strophodonta, 

 and is succeeded by another layer of pyritiferous nodules twelve feet 

 thick, and this by seven feet of calcareous shales, exceedingly rich in 

 well-preserved fossil remains, though in a portion of this layer (the argil- 

 laceous shales) fossils are abundant, it is difficult to obtain per- 

 fect specimens. In the calcareous layers, which are from two to eight 

 inches thick, fossils are most common and can usually be obtained 

 free from gangue. The following are very plentiful : 



Tropidoleptus carinatus, Conrad, Chonetes mucronata, Hall, Ortliis 

 Vanuxemi, Hall, 0. leucosia, Hall, Spirifera granulifera, Hall, Modi- 

 omorplia concentrica, Conrad, M. macilenta, Hall, Atrypa reticularis, 

 Linn, Michelinia stylopora, Eaton, Mytilarca oviformis, Con. Several 

 species of undescribed fossils in the genera Pterinea, Aviculopecten, 

 Platyostoma, Loxonema, Fenestella, Fistulipora and Alveolites. 

 C Fragmentary portions of Phacops rana y Green, and Dalmanites 

 Boothi, Green, are very common also,) but perfect specimens of the for- 

 mer are not common, and of the latter only three have been found here 

 that we are aware of. 'The articulations of Homalonotus Dekayi, 

 Green, are frequently found, /but Mrs. B. H. Wright and Wm. Buxton 

 have found the only heads (two) that we know of from this locality. 



This stratum continues to the brink of the first fall where the char- 

 acter of the rock changes from a loose calcareous shale to solid, com- 

 pact layers of a lighter color. Here occur several pot-holes, one of 

 which is two feet in diameter and the same in depth. These are near 

 the brink of a fall of nearly thirty feet In the lower portion of this 

 layer are some fine Cypricardites, with most of the species found above. 

 Then follows a calcareous stratum seven feet thick, containing many 

 crinoidal fragments. This rests npon the Encrinal limestone, 

 which is about three feet thick and forms the brink of the middle fall 

 of twenty-nine feet. This Encrinal limestone is quite hard, takes an 

 excellent polish, and being made up almost wholly of crinoidal stems 

 and rays, makes a fine polished slab. There is but one brachiopod 

 which is plentiful in this limestone. 



Pentamerella paflilionejisis, Hall, Eridophyllum Verneuilianum, 

 Ed. and H. and Diphyphyllum cigas, Rominger, are very plentiful also. 

 Among the crinoids are several undescribed species, see Dolatocrinus 



