THE EASTERN SYNCLINE. 241 



older constituents are apatite, magnetite, zircon, rutile; the newer, biotite, 

 orthoclase, albite, epidote, pyrite. Apatite is very abundant, as is also 

 magnetite; pyrite is rare. The abundant biotite shows the richest absorp- 

 tii)n colors. 



A large crystal of albite contains many small, sharp plates of biotite 

 parallel to P (001) and oo P o6 (010), and the section is so exactly parallel 

 to cc P 00 (100) that these plates are both presented edgewise to the eye. 

 It extinguishes the light at 22° and 23° with the twinning i)lane, while the 

 mica plates make with each other an angle of 94°. It is also crowded with 

 minute black nitile (f) microlites, which are broken up to an unusual extent 

 into short rods, or often into long, rigid rows of black dots parallel to P 

 (001) and oo P ob (010), and in other directions as well. The epidote usually 

 associated with the magnetite shows striking absorption — a — colorless, b = 

 pale mountain green, c = salmon color. The zircon is in small, i-ounded, 

 limpid grains, with rounded liquid inclosures, or many large elongate, stout 

 prisms with several constrictions and centrally densely dusted with black 

 grains. This agrees closely with the type of zircon occurring in the 

 gneisses as determined by K. de Kroustchofif.^ 



Across this town the western band of amphibolite is broad and well 

 marked; it commences where the town line runs north nearly to the Ware 

 River, and continues south to Fentonville, being well exposed west of E. 

 Shorley's in the middle of its length. The eastern band is wanting. 



The mica-schist extends across this town with less width than it has 

 through Ware. The great east-west fault through the south of Ware, on 

 the soi;th of whicli the rocks are thrust far to the westward against the 

 granite, seems to account for this. The schists in the northern half of 

 the town are dark, laisty, fine-grained biotite-schists, in which fibrolite is 

 exceptionally rare, but it sets in again abundantly in the southern part of 

 the town. 



MONSON. 



The same series crosses Monson, forming the crest of East Hill and 

 Moulton Hill, and crosses the State line east of Cedar Swamp Hill. It is 



' Bull. Soc. Min., Vol. XI, p. 173. 

 MON XXIX 16 



