103 



VI. VII. VIII. IX. X. 



SiO, ... 42-85 ... 37-8 ... 42-10 ... 42-94 ... 41-44 



A1 2 3 ... 10-42 ... 9-7 ... 3-28 ... 10-87 ... 6-63 



Lr..>O 3 ... ... ... ... 



Fe.,0, ... 6-27 ... 3-4 ... 8-27 ... 3-47 ... 13-87 



FeO ... 6-86 ... 7'0 ... 2-13 ... 10-11 ... G-30 



CaO ... 11-84 ... 4-1 ... 3-77 ... 9-07 ... 7'20 



MgO ... 9-01 ... 22-9 ... 30-65 ... IG'32 ... 18-42 



MnO ... ... ... -70 ... tr. 



K,0 ... 1-611 ( 0-15 ... 0-93 



Na,0 ... 1-G5 ' " ( 0-aO ... 0-24 



HoOandCO, 8-58 14-0 7-73 G-09 5-60 



99-09 99-7 100-53 99-95 100-63 



Sp. Gr. 2-81 2-82 2-88 



I. Dunite. Dun Mountain, New Zealand. Composed of olivine with 



chromite or picotite. Reise seiner Majestjit Fregatte Novara. Geol. 

 Theil., Band I., p. 218. 



II. Olivine-enstatite-rock (Saxonito). St. Paul's Rocks. Voyage of 



If. M.S. Challenger. Narrative, Vol. II., Appendix B. Analysis by 

 Sirocz. Contains also 0-51 NiO. 



III. Olivine-enstatite-augite-rock (Lherzolite). Baldissero. Monte Rossi, 



Piedmont. Composed of olivine (G7 per cent.) enstatite, chrome- 

 diopside, picotite and pyrite. Cossa ; quoted from ROTH'S Beitriige 

 zur Petrogrnphie, &e., Berlin, 1884. 



IV. Olivine-augitc-rock. Picrite (Pala?opicrite). Sclnvarze Stein, Dillgegend, 



Nassau. Contains also '162 NiO and traces of Cu, Bi, Co. S, and 

 P 2 a . Oebbeke ; Ein Beitrag zur Kenntniss des Palreopikrits. 

 Inaug. I)iss. Wurzburg, 1877. 



V. Picrite (Tscheruiak) Gumbelberge. Olivine and diallage in a ground- 



mass composed of diallage, biotite, magnetite, calcite, microlites and 

 glass. Olivine more or less serpentinised. This is one of the 

 original picrites. TSCHERMAK ; Porphyrgesteine Osterreichs. 

 Wien, 1869, p. 247. 



VI. Altered Picrite. Sohle. This rock contains 5-88 of C0 2 . The 



olivine is represented by pseudomorphs of calcite and a basic silicate 

 containing lime, magnesia, alumina and alkalies. The alteration has 

 been accompanied by the removal of magnesia and the introduction of 

 lime. TSCHERMAK ; Porphyrgesteine, &c., p. 252. 



VII. Altered Picrite (Palseopicrite). Inchcolm. JUDD ; Q.J.G.S., Vol. 



XLL, p. 400. Analysis by WALLER. 



VIII. Scyelite. JUDD ; Q.J.G.S., Vol. XLL, p. 402. Analysis by H. R. 



MILL. 



IX. Hornblende-picrite. Boulder near Ty Croes, Anglesea. BONXEV. 



Q.J.G.S., Vol. XXXIX., p. 2f>G. Analysis by J. A. PHILLII-S. 



X. Hornblende-picrite, Schrieshoim. Quoted from last-montioned paper. 



