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FREDERIC II. LAHEE 



if they i\o not quite, (ouch one another. Many of the grains are an- 

 gular: none is conspicuously rounded, and they do not seem to have 

 been rounded before mctamorphism. Of the two minerals, sericite 

 and chlorite, the latter is most plentiful. The chlorite is least likely 



Fig. [3. -Section of a typical 

 psammitic member of the Lyman 

 series. Enlarged ia diameters. 



Fig. 14. — Section of a pot 

 phyritic pebble of the "Parker 

 Hill dark, schist." Enlarged 15 

 diameters. 



to have parallel orientation. Another specimen from farther north- 

 east near this horizon exhibited similar characters in thin section. 



Parker Hill dark 

 schist. The specimen 

 from which the sec 

 tion was cut was ob- 

 tained northeast of 

 Parker Hill along the 

 strike oi the rock ex- 

 posed in the Lisbon 

 Lyman road, and it is 

 thought to belong to 

 the same horizon. 

 Thephyllite is a small 

 angular fragment in a 

 whitish clastic matrix of the kind just described. It is porphyritic 

 (Fig. 14), having small phenoerysts (o. 13 1.0 mm.) of plagioclase. 

 often with well-preserved crystal form, distributed in a very tine 

 groundmass of plagioclase and chlorite. The phenoerysts do not 



FlG. 15.- Tart of the "egg conglomerate" where 

 the majority of the pebbles arc angular and snbangnlar. 

 Photograph by K. \V. Sayles. 



