CONTENTS 



Genera] description 5 



Age and structure 7 



Correlation 9 



LLUSTRATIONS. 



Pl. I. Maji of Grey lor lv and Hoosac Mountains Frontispiece. 



II. General map showing relation of the Greylock series to the Hoosac mountain rocks. ... 10 



III. Structural relations of the Hoosac series 1 4 



Fig. 1. The Stamford dike, showing Cambrian conglomerate deposited in dike fissure 11 



2. The Stamford dike, plan 11 



3. ( lorrelated columns of the Hoosac and Greylock rocks 13 



4. Anticlinal arcli across I loosic river between North Adams and Briggsville l."> 



5. Ideal sectiou east of < Iheshire, showing lateral transition of limestone to schist 17 



li. Diagram of structure, summit of the hut tress 22 



7. ('rum | dec! structure in albitc.-schist 23 



S. Map showing the \ arying character of. Cambrian rocks around the Hoosac core .'il 



3 



