246 MINERALOGY AND LITHOLOGY. 



Fig. 6. A section of the Troy granite, in polarized light, showing a grain of mi- 

 crocline and the characteristics of the minerals which compose the 

 Concord group of granites — page 195. x 50 



Plate XI. 



Fig. I. A section of the easily disintegrating Conway granite — page 195. x 30 



Fig. 2. A section of the Antrim granite, showing the appearance of the garnets 



which are commonly found in the granites — page 197. x 30 



Fig. 3. A section of the Mt. Carrigain granite, showing the microscopic pegma- 

 tite which characterizes it — page 201. x 200 



Fig. 4. Centre of a mica concretion in the pudding granite from Craftsbury, 



Vt. — page 203. x 6 



Fig. 5. A section of augite sienite from Jackson, showing the process of forma- 

 tion of uralite — page 205. x 50 



Fig. 6. A grain of titanic iron in a section of the augite sienite from Jackson — 



page 205. X 50 



(See, also. Fig. i on PI. 7, which is a section of augite sienite from another lo- 

 cality.) 



Plate XII. 



Fig. I. A grain of quartz in a section of sienite from Columbia. The quartz is 

 in contact with a crystalline grain of calcium carbonate, and encloses 

 a multitude of cavities, each of which is partially filled with liquid 

 carbonic acid — page 207. x 350 



Fig. 2. A section of argillitic mica schist from Woodsville — page 219. x 600 



Fig. 3. A section of metamorphic diorite from Pittsburg — page 227. x 50 



Fig. 4. A section of metamorphic quartz diorite from North Lisbon — page 229. x 50 

 Fig. 5. A section of a half fragmental quartz from Newcastle — page 239. x 30 



Fig. 6. A section of the Connecticut red sandstone — a fragmental rock— page 



239- X 30 



