HANDBOOK FOR THE DEPARTMENT OF GEOLOGY. 513 



1. Types of crystalline rocks — Continued. 



(3) Massive structure: 



Diabase, Goose Creek, Loudoun County, Virginia. 28116 



(4) Stratified structure : 



(a) Limestone, East Conskohocken, Pennsylvania. 26983 



(6) Sandstone, Summit County, Utah. 70595 



(5) Foliated or schistose structure : 



Gneiss, Lawrence, Massachusetts. 26547 



(6) Fluidal or fluxion structure : 



(a) Quartz porphyry, Milton, Massachusetts. 35946 



(b) Rhyolite, High Rock Canon, Nevada. 35441 



(7) Porphyritic structure : 



(a) Porphyrite, Shasta County, California. 70594 



(b) Quartz porphyry, Marblehead Neck, Massachusetts. 35960 



(8) Vesicular structure : 



(a) Basalt, Ice Cave, Butte, Utah. 70592 



(b) Andesite, Portugal. 37926 



(9) Amygdaloidal structure: 



(a) Melaphyr, Brighton, Massachusetts. 35940 



(b) Melaphyr, Oelnitz, Saxony. 36133 



(10) Slaggy structure : 



Basaltic lava, Hawaiian Islauds. 35853 



(11) Concretionary structure : 



Kugeldiorite, Corsica. 36054 



(12) Dendritic" structure : 



Limestone, England. 29113 



(13) Botryoidal structure: 



Hematite, Cleater Moor, Cumberland, Eugland. 36085 



(14) Fibrous structure : 



(a) Asbestus, Charlottsville, Virginia. 28109 



(b) Gypsum, Nova Scotia. 37624 



(15) Radiated structure: 



Wavellite, Garland County, Arkansas. 36104 



(16) Columnar structure : 



Columnar calcite. . 36787 



(17) Brecciated structure: 



Felsite breccia, Marblehead Neck, Massachusetts, 35952 



(l^) Cavernous structure: 



Dolomite, Chicago, Illinois. 27508 



2. Typos of vitreous rock : 



I. Black Obsidian, Mono Lake, California. 29631 



(1) Fluidal or fluxion structure: 



Obsidian, Glass Buttes, Oregon. 35921 



(2) Vesicular structure : 



Obsidian Pumice, Mono Lake, California, 29630 



(3) Porphyritic structure : 



Porphyritic Obsidian, Yellowstone National Park. 28888 



(4) Perlitic structure : 



Perlite, Schemnitz, Hungary. 36134 



(5) Spherulitic structure : 



Obsidian, Yellowstone National Park. 18969 



(6) Capillary structure : 



Peles Hair, Volcano of Kilauea, Hawaiian Islands. 8902 



H. Mis. 129, pt. 2 33 



