REPORT OF THE DIRECTOR I919 I25 



1 Zone of Climacograptus typicalis, Glossograptus quadrimucro- 

 natus approximatus and Lasiograptus eucharis. 



2 Zone of Dicranograptus nicholsoni. 



3 Zone of Climacograptus pygmaeus and Glossograptus quadri- 

 mucronatus longispina. 



To this is finally to be added, from the black shale of the Black 

 River valley, the Deer River shale and Atwater Creek shale: the 

 zone of Climacograptus typicalis posterus and Glossograptus quad- 

 rimucronatus, forma typica. 



This zone also contains Diplograptus nexus and C 1 i- 

 macograptus pygmaeus. It indicates a northeastern 

 invasion. 



The Lorraine beds contain graptolites but these are, for the most 

 part, scattered and the beds not developed into graptolite shales. 



Summarizing all the zones and subzones here enumerated, we get 

 the following: 



Table of Graptolite Zones of the Ordovician Shale Belt of New York 



1 Schaghticoke shale 



I Zone of Dictyonema flabelliforme 



II Zone of Staurograptus dichotomus 



2 Deep Kill shale 



III Zone of Clonograptus fliexilis and Tetragraptus 1 Tetragraptus 



IV Zone of Phyllograptus typus and Tetragraptus |- beds of 



quadribrachiatus (zone inferred) J Raymond 



V Zone of Didymograptus 



a Subzone of Didymograptus nitidus and Didymograptus 



patulus 

 b Subzone of Didymograptus extensus and Goniograptus 



thureaui 



VI Zone of Didymograptus bifidus 



a Subzone of Goniograptus geometricus and Phyllograptus 



anna 

 b Subzone of Didymograptus similis and Phyllograptus 



typus 



VII Zone of Diplograptus dentatus and Phyllograptus angustifolius 



a Subzone of Climacograptus pungens and Didymograptus 



forcipiformis 

 b Subzone of Phyllograptus angustifolius and Retiograptus 



tentaculatus 

 c Subzone of Desmograptus and Trigonograptus ensiformis. 



3 Normanskill shale 



VIII Zone of Nemagraptus gracilis 



IX Zone of Corynoides gracilis 



4 Magog shale, Van Schaick Island and Mechanicville shale 



X Zone of Cryptograptus tricomis insectiformis and Climaco- 



graptus caudatus (Probably two subzones) 



