T. jS. Huni—N'oies on QranUic EocJcs. 



bvT. SterryHln 



^16. It is in the series of micaceous schists with interstrati- 

 lied gneisses (§ 6) which I have elsewhere provisionally desig- 

 nated the Terranovan series,* that I have seen concretionary 

 granitic veins in the greatest abundance and on the gTandest 

 scale. This stratified system, which is well seen in the Wbite 

 Mountains, appears to extend southward to Long Island Sound 

 and northeastward beyond the limits of Maine. It is in tni^^ 

 state that I have particularly studied the granitic veinstones ot 

 this system, whose history may be illustrated by a few e--^^'"- 

 pies from notes taken , ^ - -^ ■ - ^ -.i. .i.. . 



near the t 



and hornblendic, passing into micaichis. ww . -^ - ^^ , 



mto well-marked gneiss on the other, and dipping to the b. ^ 

 angles of from 15° to 40°. Very similar beds are found in if 

 adjoming town of Topsham, and in both places they include 

 numerous endogenous granitic veins The course of these i- 

 generally N.W., or at right angles to 'the strike, thougli 

 sionally for short distances with the strike, and inters;: 

 between the beds; the veins vary in breadth from a few 

 to sixty feet, and even more. They generally consist in - 

 part of orthoclase and quartz, with some mica and touriu^ ^ 

 and offer in the associations and grouping of these mi"*'';;; 

 many peculiarities, which are met with not only in difl«v!>; 

 veins but in different parts of the same vein. In some ca^e.- 

 colorless vitreous quartz predominates greatly, and encloses ci.^ 

 tals of milk-white orthoclase, often modified, and from one 

 several inches in diameter. At other times pure vitreo^ 

 quartz forms one or both walls or the center of the vein, or eu* 

 ^1 arranged in bands parallel with the ^ide.^ of the vein, aj^ 



sometin 



-.. -Au 



