356 



PROCEEDINGS OF THE ACADEMY OF 



[Nov., 



Fig. 2. — Quartz diabase, three miles northwest of Lebanon. (SHde 1, X 15). 



Structure ophitic; latbs of labradorite, euhedral augite, with interstitial 



graphic intergrowths of quartz and orthoclase. 

 Fig. 3. — Edge of fragment of basalt in glass, separated by a vein of calcite. One 



mile southwest of Jonestown. (Slide 19, X 15). 

 Fig. 4. — Basalt glass, amygdaloidal ; one mile southwest of Jonestown. (Slide 



20, X 25). Shows perlitic structure in the glass, and a calcite amygdule 



(white). 

 Fig. 5. — Ainygdule of quartz in basalt; one mile southeast of Jonestown. (Slide 



,27, X 25). 

 All in ordinary light. 



