PLATE III. 



Fig. 1. Peridotite, — Lherzolite. Pcltusk, Poland. 



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This shows a portion of a section with two chondi-i at the base of the figure, while the remaining 



upper portion is made up of an aggregate of chondri, olivine, enstatite, diallage, pyrrhotite, 



and iron grains. The larger and darker c.hondrus is composed of aggregately polarizing 



fibrous enstatitic material. This chondrus shows rounded indentations, and on its left is 



another form, composed of alternating colorless enstatite ribs and bands of gray base with 



minute iron granules. The dark portions of the figure represent the iron and pyri-hotite, and 



the yellowish-brown the ferruginous staining 94, 95 



Fig. 2. Peridotite, — Lherzolite. Poltusk, Poland. 



This displays the structure of a chondrus composed of olivine, enstatite, iron, etc., cemented by a 

 gray base. This chondrus occu]iies the chief portion of the figure, but towards the bottom its 

 gradual pas.sage into the grouudmass is shown. The ferruginous materials are colored as 

 in Fig. 1 " W, 95 



« Fig. 3. Peridotite, — Lherzolite. Pultusk, Poland 



The brownish-black central portion is pyrrhotite surrounding a steel-gray pear-shaped mass of 

 metallic iron. Surrounding the pyrrhotite is the chondritic grouudmass of the meteorite, 

 partially stained yellowish-brown 94, 95 



Fig. 4. Peridotite, — Saxonite. Waconda, Kansas. 



This shows a mixed granular grouudmass of olivine, enstatite, iron, and pyrrhotite, which is 



more or less stained a yellowish- and reddish-brown from the oxidation of the iron 93, 94 



Fig. 5. Peridotite, — Lherzolite. Estherville, Emmet Co., Iowa. 



This shows a grayish and a greenish-yellow groundmass of olivine, enstatite, and diallage, with 



dark-colored iron and pyrrhotite, surrounding a larger crystal of diallage 97-101 



Fig. 6. Peridotite, — Lherzolite. Estherville, Emmet Co., Iowa. 



This represents a semi-sponge-like mass of iron and pyrrhotite with enclosed grains of olivine, 

 diallage, and enstatite. On the left is figured a crystal of enstatite with its inclusions and 

 characteristic cleavage ; while on the right is a crystal of diallage showing its cleavages. 

 The yellowish-brown ferruginous staining is to be seen in some portions of the figure. . . . 97-101 



