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NEW YORK STATE MUSEUM 



SUCCESSION OF FOSSIL FAUNAS 

 Camillus shale 



We know of no traces of organisms in these deposits except 

 an occasional ostracode shell (Leperditia) and a trail made on 

 the soft mud by such an organism. The sediments were laid 

 down in a sea too shallow and too strongly saturated with brine 

 and alkalis to encourage the existence of life. 



Bertie waterlime 

 The fauna of these beds is that peculiar association of crusta- 

 ceans which has made this horizon one of the most interesting 

 in the entire series of the New York formations. Occasionally 

 in the outcrops and more freely in the loose blocks of this rock 

 scattered over the country south of the line of outcrop, are 

 specimens of Eurypterus r e m i p e s Dekay and Cerat- 

 iocaris acuminata Hall, with abundant Leperditia s, 

 Lingulas and an occasional Orbiculoidea. Westward of this 

 region specially in the exposure in the quarries of the Buffalo 

 Cement Co. at Buffalo, and eastward in the towns of Sauquoit 

 and Litchfield, Herkimer co., these crustaceans with others are 

 found in great abundance and perfection, but in the intervening 

 region they have thus far proved of rarer occurrence. The fauna 

 of these merostome crustaceans is widely known as one marking 

 the closing stages of Siluric time through northern latitudes on 

 both hemispheres. 



Cobleskill shale and dolomite 



The fauna here is sparse but indicative of the relation of the 

 horizon to its more typical eastward outcrops. The list of species 

 at present known is : 



Eurypterus, occasional fragments Spirifer eriensis Grabau 

 Leperditia alta Conrad Cyathophyllum hydraulicum Simp- 



h. scalaris Jones son 

 Whitfieldella sulcata Vanuxem 



Oriskany sandstone 

 This rock carries no fossils in this district. At Union Springs, 

 Oayuga co. is the nearest point where the characteristic fauna 

 of the arenaceous deposits is developed with Spirifer are- 



