Upper 

 Gallery. 



Wall-case 2. 



158 



VOLCANIC ROCKS OF CHATHAM ISLAND. 



106. — Basaltic lava from the surface of the stream, 

 slightly scoriaceous, and twisted and convoluted by flowing 



while in a viscous state. 

 Cove. 



Dead 



s 



107. — Vesicular and scoriaceous lava, Dead Man's 



Cove. 



108. — SCORIACEO 



u 



Evans' Well 



109. Volcanic slag or cinder, mixed with fine-grained, 



friable, brown-coloured tufa or peperino : from the summit 



of the crater. 



110. Cellular basalt, containing olivine and calc 



spar. — North Hill. 



HI. Basaltic lava, with numerous small vesicles. 



Road from First Well, Charles' Island. 



112. Cellular basalt, with olivine, and minute crys- 

 tals of calc spar. — Salt Lake, Chatham Island. 



113. 



Cellular basalt, some of the cells containing 



olivine, and others crystals of calc spar. — From the bottom 



Q 



114. 

 115. 



Evans' Well. 



ONE, Dalrympl 



116. Porphyritic greenstone, composed of crystals of 



/< 



glassy felsp 

 : of Pico d'l 



and weathered crys- 



From near the 



May 



Cape de Verde 



117. 

 group. 



118. — Semi opal between two layers of chalcedony, 

 the lowest of which has been formed upon crystals of calc 

 spar, which have disappeared leaving their casts. — Hicaron 



Island, Coiba. 



119. — Obsidian, with sphcerulitic concretions, shewing an 

 olive- green colour, on the thin cutting edges, by transmitted 



l-o 



Mexico 



120. 



Katteu 



> i 





f 



u 





.-Far 



- 

 il s em 



i it tie v 





j|l A * 



- 



-«••* 1*%^ 





■*S!f4 



proWi 

 •pop 



• 



4. 



to*,. 



.: 







■ *» . 







V I 





\ 



•;i 



i f. : 



H 



: 





