GEOLOGY AND PALEONTOLOGY OF THE SCHOHARIE VALLEY 209 



Feet 



Esopus and Schoharie grits. 300 



These are practically indistinguishable except by 

 the fact that the Schoharie member (about 200 

 feet thick) shows good cleavage while the 

 Esopus " checks " readily into small fragments. 

 Good exposures of both formations are found 

 along the Newman road which crosses Becraft 

 mountain longitudinally. Both are dark silici- 

 ous muds with scarcely any fossils and much 

 affected by cleavage. The following fossils have 

 been listed from the Schoharie : 



Dalmanites anchiops 

 Phacops cf. bombifi'ons 

 Coelospira cf. Camilla 

 Chonetes cf. arcuatus^ 



Oriskany quartzite 1-2 



These are silicious limestones and quartzite beds 

 v/hich weather brown leaving the fossils as 

 molds. Much chert is present. Few exposures 

 in situ are met with, the best one being on the 

 Newman road before it ascends the knoll of Eso- 

 pus shales. In the meadows bordering the 

 swamps around this knoll are loose fi^agments 

 of this rock from which the characteristic fossils 

 may be obtained. The commoner species are : 



Cyrtolites expansus Hall 

 Diaphor'ostom.a desmatiim Clarke 

 D. ventricosum Conrad 



Pterinopecten proteus Clarke 

 Rensselaeria ovoides Eaton 

 Megalanteris ovalis Hall 

 Coelospira dichotoma Hall 

 Leptocoelia flabellites Conrad 

 Splrifer arenosus Conrad 

 Sp. murchisoni Castelnau 



Chonetes hudsonicns Clarke 

 Anoplia nucleata (Hall) 

 Orthothetes becraftensis Clarke 

 Leptositrophia oriskania Clarke 

 Braehyprion majiis Clarke 

 Leptaena rhomboldalis (Wilckens) 

 Crania piilchella Hall & Clarke 



The total number of species listed from this fauna by Clarke 

 is 113. Of these 25 are Helderbergian, 24 occur in the normal 

 Oriskany of Schoharie and the Helderbergs, 10 are found in the 

 Onondaga and 1 in the Hamilton. The remainder are peculiar 

 to it. 



'Clarke, J. M. Oriskany Fauna of Becraft Mountain, Columbia Co. N. Y. 

 N. Y. State Mus. Mem. 3. 



