GNEISS AND LIMESTONE CONTACT PHENOMENA 277 



''Pyroxene-titanite aplite" from the Peru line. Plagioclase 

 (/3d = 1.536; a'p = 1.531; 7'd = 1.542; Aiiio), microcline, quartz, 

 hornblende (/3d = 1.676; Feji), clinopyroxene (q;d = 1.695; /^d = 

 1.706; 7d = 1.724; He4o), titanite, biotite (/3d = 70 = 1.647; 80 

 per cent Fe-comp.), epidote (/3d = 1.750; 2>3 P^r cent Fe-comp.), 

 apatite. 



Intrusive layer in limestone N. of Becket Station. Quartz, 

 plagioclase (Ann), microcline, clinopyroxene (/3d = 1.700; Hejj), 

 hornblende (/3d = 1.680; Fe^^), grossularite-andradite (no = 1.80; 

 40 wt. per cent andradite), calcite, epidote. 



Band in the gneiss, railroad cut W. of Becket Station. Quartz, 

 microcline, clinopyroxene (colorless; 0:0 = 1.685; (3d = 1.690; 

 7d = i.7i4; 7Ac = 4i°; Heas), actinolite (pale green; /3d = 1.638; 

 Fei,), graphite, calcite, titanite. 



Clinopyroxene gneiss near limestone in the valley of Goose 

 Pond Brook. Clinopyroxene (colorless, /3d = 1.681 =1=0.001; Hen), 

 amphibole (/3d = 1.633=^=0.002; Fei4), quartz, microcline, plagioclase 

 (/3d = 1.534; Any), epidote (/3d = 1.730; 18 per cent Fe-comp. or 

 9 wt. per cent Fe203). Occasional scapolite (cod = 1.572 =1=0.001; 

 en = 1.547='= o.ooi; about MesoMago) and black tourmaline. 



Dark band in the gneiss South of Benson Pond. Clinopyroxene 

 (j3d = 1.695; Hcji), hornblende (0:0 = 1.672; /3d = 1.685; 70 = 1.695; 

 Fe^g), plagioclase (zoned, Auiy to An^), quartz, microcline, titanite, 

 biotite (/3d = 70 = 1.635; about 65 per cent Fe-comp.). 



Dark band N. of Benson Pond. Plagioclase (zoned, An23 to 

 Ariie), hornblende ((3o = 1.660; Fe36), biotite (/3d = 7d 1.642; 75 

 per cent Fe-comp.), quartz, epidote, titanite, apatite. 



Dark band in the gneiss N. of Becket Station. Biotite (jSo = 7o = 

 1.620; 50 per cent Fe-comp.), hornblende (j3o = 1.650; Fe29), 

 plagioclase (/3d = 1.536; o!'o = i.532; 7'd = i.54i; Aujo), microcline, 

 quartz, epidote. The quantity of epidote is considerable. 



''Lee quartz diorite" from west end of Goose Pond. Plagioclase 

 (zoned, Auja to Auzp), hornblende (/3= 1.665 appr.; Fe4o), cum- 



angle 7 Ac however, does not accord with the series, being 58° instead of 46° 20'. 

 Probably this clinopyroxene contains a certain amount of aegirite, although its very 

 faint pleochroism (a = pure green, 7 = brownish) indicates that the amount may be 

 small. — In another specimen was found a clinopyroxene He6o(|8D = 1-721). 



