ILLUSTRATIONS, 



Plate I. Coign of Williston Hall at Amberst College, showing conglomerate-giifiss from th<i 



Monsou quarry 64 



II. Thin sections 106 



Fig. 1. Sahlite cban;;ing to tremolite 106 



2. Dolomite changing to serpentine 106 



3. Enstatite crystal altered to serpentine, cut parallel to (001 ) 106 



4. Garnet, with complex border, from pegmatite 106 



III. Thin sections 208 



Fig. 1. Leyden argillite changed to cUiastoIite schist in contact on tonalite 208 



2. Cordierite twins, from cordierite-granite 208 



3. Diorite, from Packards Mountain, Prescott 208 



4. Contact of diabase-amygdaloid and clayey limestone 208 



IV. Map of the Devonian rocks of the Bernardston series and of the faulted synclinc of 



Silurian schist in Northfield Mountain 260 



v. Sections of amphibolites derived from limestone 302 



VI. Sections of amphibolites probably derived from limestone ' 306 



VII. Tourmaline dendrites in granite, Leeds -■- 316 



VIII. Vertical wall of diabase at the quarry for road material in the east of Greenfield 424 



Villa. Details of trap ridge east of Greenfield 426 



VIII6. Inclusion of mud in upper surface of trap sheet 428 



VIIIc. Thin sections of material from Greenfield and Merideu "ash bed " 430 



IX. Geological map and sections of the Mount Holyoke-Mount Tom range, with the i)os 



terior diabase sheets, the tuff, and the volcanic cores 446 



X. Patterson's quarry, in north part of South Hadley, showing veneeiing of sandstone 



on Black Rock core ■• 488 



XI. Map of preglacial drainage and <lrift strife !f-^- SIO 



XII. Sections in Amherst House cellar, showing interglacial beds 550 



XIII. The great serpent esker in Pelham 578 



XIV. Diagram of the lake-shore and lake bottom profiles of the Connecticut lakes 656 



XV. Sections at the Camp Meeting cutting, on the north line of Northampton, showing the 



readvances of the glacial ice 678 



XVI. Surface of ice-contorted clay, smoothly cut with a knife, east of ,1. Ryan's house. Hat- 

 field B90 



XVII. Joints and faults in laminated clay, produced by the weight of the ice 692 



MON XXIX ii ^'*'" 



