512 



FREDERIC H. LAHEE 



Fig. 17. — Ilmenite crystal nearly 

 inclosed in biotite. (See Fig. 18.) 12 

 diameters. 



Fig. 18. — ^Outline sketch of Fig. 17. 

 B, biotite. I, ilmenite. The dotted 

 lines represent the edge of what used 

 to be a quartz coating on the ilmenite. 

 Cf. Fig. I. 



Fig. 19. — Biotite and garnet meta- 

 crysts. (See Fig. 20.) 25 diameters. 



Fig. 20. — Outline sketch of Fig. 19. 

 B, biotite. G, garnet. The dotted 

 lines represent the edges of the garnet 

 crystals before replacement by biotite. 



