1870.] T. S. HUNT — ON GRANITIC ROCKS. 401 



terfield, Middleton aud Haddam, seem from descriptions, and 

 from their mineral constituents to be similar to those of Maine, 

 already mentionad. With the exception of Royalston however 

 these localities are as yet only known to me from specimens and 

 descriptions. It ii noteworthy that at this last the finely-crystal- 

 lized beryls are directly imbedded in vitreous quartz, and the 

 same is the case with the blue and jireen tourmalines of Goshen. 

 A remarkable example of a vein of this character occurs in Buck- 

 field, Maine, described to me by Prof. Brush, where large isola- ' 

 ted crystals of white orthoclase, nearly colorless muscovite aud 

 brown tourmaline occur in a vein of vitreous quartz. At Paris 

 and at Hebron, Maine, tourmalines are found penetrating crystals 

 of quartz. The flattened tourmalines and garnets found in mus- 

 covite at several localities in New England, are well known to col- 

 lectors, and a curious example of enclosure has been observed by 

 Prof. Brush at Hebron, where crystals of muscovite are encased 

 in lepidolite. 



§ 2o. The following list includes the principal mineral species 

 found in these granitic veins in New England : apatite, ambly- 

 gonite, triphylline, autunite, yttrocerite, orthoclase, albite, oligo- 

 clase, spodumene, iolite, muscovite, biotite, lepidolite, cookeite. 

 chlorite, chlorophyllite, garnet, epidote, tourmaline, beryl, zircon, 

 ([uartz, chrysoberyl, automolite, cassiterite, rutile, brookite, uran- 

 inite, columbite, pyrochlore, scheelite, and bismutite. As I am 

 not aware that chlorite has hitherto been mentioned as a constitu- 

 ent of these veins, it nuiy be said that it occurs in one at Albany, 

 Maine. To the above should probably be added the rare species 

 nepheline, cancrinite and sodalite, which have long been known in 

 boulders of a granite-like rock in Maine. According to informa- 

 tion given me by Prof. Brush, green claeolite with white ortho- 

 clase and black biotite occurs in a granitic vein twenty feet in 

 breadth, lately observed in the northwest jmrt of Litchfield, 

 Maine. 



§ 24. "We have seen that these endogenous veins are found 

 alike in the gneisses, mica-schists, limestones and quartzose strata 

 • 'f tills region. They are also met with in the eruptive granites, 

 small fissures in which are sometimes filled with coarsely crystal- 

 line orthoclase, smoky quartz, various micas and zircon. Examples 

 of this are seen in the granites of Ilampstead, New Brunswick, 

 and Mt. Uniacke, Nova Scotia. The fine green feldspar of Cape 

 Ann, Mass., and the miens, cryophyllite and lepidomelnne with 



