250 ANNALS NEW YORK ACADEMY OF SCIENCES 



show good crystal outline. \n thin section under the microscope, the 

 rock shows a distinctly foliated structure and is seen to be made up of an 

 aggregate of sericite and quartz. In it are large crystals of garnet, biotite 

 and staurolite. The latter mineral makes its first appearance but is not 

 as yet very abundant. 



A specimen collected two and one-half miles east of the above locality 

 shows abundant biotite and an occasional garnet cr3^stal embedded in a 

 fine-grained matrix. This matrix resolves itself under the microscope 

 into an aggregate of quartz and sericite, with abundant iron oxide scat- 

 tered through it. A little plagioclase and a few small tourmalines are 

 also present. The rock shows a distinctly foliated structure (PI. XIV, 

 Fig. 3). It is evident that the metamorphic changes here have not 

 reached quite so advanced a state as in the case above. Most but not all 

 of the biotite crystals are oriented parallel to the foliation. 



A specimen from an outcrop occurring three and one-half miles east of 

 the Clove Valley showed a medium fine texture and distinctly foliated 

 structure. Abundant garnet and biotite show in the hand specimen. 

 Under the microscope, the main mass of the rock is seen to consist largely 

 of quartz and sericite. The biotite is full of quartz inclusions. 



A specimen collected a short distance east of the above locality shows a 

 marked schistose structure. It has a silky luster due to the presence of 

 numerous fine sericite flakes. Garnet and biotite are prominently devel- 

 oped. In thin section, the sericite flakes all show more or less parallel 

 alignment to the foliation. Quartz occurs in small grains interspersed 

 between the sericite. Biotite is present in considerable amounts in fairly 

 large flakes embedded in this matrix. The same is true of garnet. An 

 occasional staurolite crystal has also been developed. Some chlorite is 

 present. The texture in this specimen is a good deal coarser than any 

 described thus far. 



A half mile east of this locality near the western contact of the Dover- 

 Pawling limestone with the schists the rock is quite coarsely crystalline. 

 Garnet, biotite and abundant staurolite crystals can be readily made out 

 embedded in a fine matrix which has a silky luster due to the abundant 

 presence of muscovite. The rock is a typical staurolite-mica schist. In 

 thin section, the matrix is seen to be made up of medium-grained aggre- 

 gate of muscovite and quartz, with an occasional grain of orthoclase and 

 plagioclase (PI. XIV. Fig. 4). The quartz occurs in fairly large grains 

 at times. The flakes of muscovite are oriented parallel to the foliation. 

 Biotite is also abundant and occurs in larger flakes than the muscovite 

 also oriented parallel to the foliation. Staurolite and garnet with good 

 orystalline outlines occnr abundantly interspersed in this matrix. T'hey 



