BERNAEDSTOIf SEEIES OF UPPEK DEVONIAN. 



285 



The mica-schist in Xorfhfield. — East of the river only a .single limited 

 outcrop of mica-schist occur.s, half a mile below the village, just opposite 

 Grass Hill and 200 rods from the nearest outcrop of hornblende rock on the 

 west side of the river. It agrees in texture with the lowest ])eds of schist 

 on the west of the Connecticut, is fine-grained, and carries few accessories. 

 It abounds in flattened ca^'ities, which seem to be the obscure traces of fossil 

 shells, but they are wholly indeterminable, if, indeed, they be of organic 

 origin at all. Upon the joint faces are abundant weathered crystals of a 

 flesh-colored zeolite, apparently ehabazite. The .exact locality is by the 

 brook crossing at a mill pond near the house of A. Billings. 



THE ORIGINAL, CHAKACTER OF THE SERIES AXD ITS METAMORPHISM. 



The section below seems to me to represent the succession of the beds 

 under consideration, the newest above. 



Beds of the Bernardston series. 



Upper Devonian : 



Mica-schist series . . 



1. Mica-scliist. 



2. Ampliibolite. 



3. Mica-schist. 



4. Amphibolite. 



5. Mica-.schist. 



6. Amphibolite. 



7. Mica- schist. 



8. Quartzite. 



9. Amphibolite and magnetite, local, derived from the 

 limestone. 



10. Limestone, with fossils. 



11. Amphibolite, derived from the limestone. 



12. Quartzite-conglomerate. 



13. Leyden argillite. 



14. Conway mica-schist. 



Originally heavy beds of shale (13) were followed by a gi-eat series of 

 feldspathic sandstones and conglomerates (12-8), which contained a band 

 of crinoidal limestone, with here and there a local development of ii'on ore 

 near its surface. Above this was an extensive series of .shales (7-1) with 

 several intercalated beds of impure limestone. The first series has changed 

 into a crumpled and cleaved phylHte, to which the name argillite has been 

 for a long time applied. The second series has passed tlu'ough all the 



Quartzite series 



Upper Silurian : 



