EARLY DEVONIC HISTORY OF NEW YORK AND EASTERN NORTH AMERICA 39 



Grande Greve limestones 



This series of strata is divisible as follows in descending order : 



3 Pure gray blue limestones without chert 



2 Impure gray limestones with chert 



I Drab hydraulic limestones with pure," heavy-bedded limestones 

 above. 



I We conceive the lowest beds of this series to be represented by drab 

 and yellowish sandy hydraulic limestones in thin, irregular plates and carry- 

 ing rare layers and nodules of chert. These beds are exposed along the bed 

 of Dolbel brook at 

 Grande Greve and at 

 the bottom of the 

 coulee at Shiphead. 

 At the latter point 

 they lie below the j^^ 



ypj-y characteristic Secllon across the Forillon at Grande Greve and the Kings road to Cape Rosier cove. 



■ ^ . 1 • 1 ■ Elevation of Mt St Alban 1170 feet 



green layers which 



Logan makes the summit beds of his division 7. In these hydraulic layers 

 is the first well defined exemplification of the fauna of the Grande Greve 

 series. Specially abundant isChonetes canadensis, covering entire 

 slabs of the rock; Leptostrophia irene and L. magnifica are 

 also very common. The overlying purer limestones free from or with little 

 chert carry Hipparionyx proximus, Rhipidomella m u s c u- 

 1 o s a, R. 1 o g a n i, M e g a 1 a n t e r i s t h u n e i, C a m a r o t o e c h i a p 1 i o- 

 pleura, all in abundance and affording a very striking combination. With 

 them is the remarkable trilobite Gaspelichas grandegrevensis. 

 For the most part these beds are buried under the* higher strata and it is 

 only along Dolbel brook that exposures are well shown above the dolo- 

 mitic layers beneath. 



On the shore at Lehuquet's cove east of the Grande Greve these purer 

 limestones appear in force, attaining a thickness of 50 feet. Here they 

 present the chocolate brown color characteristic of some of the purer layers 



