242 



A NATURALIST IN THE PACIFIC 



CHAP. 



Second Order of the Olivine-Basalts. 



Characters. — Olivine in abundance. Felspars of the groundmass 

 in flow-arrangement. 



Formula. — OHv., matr., cop., flu. 



Sub-order. 



Pyroxene 



of the 



groundmass. 



4- 



Granular 

 {gran. ) 



5- 

 Prismatic 

 (prism.) 



Ophitic 

 [pph.) 



Section. 



Presence or 

 absence of plagio- 

 clase phenocrysts. 



Plagioclase 



phenocrysts 



{phen.) 



No plagioclase 

 phenocrysts 

 {non-phen. ) 



9. Phen. . . 



10. Non-phen. . 



11. Phen. . . 



12. Non-phen. . 



Genus. 



Character 



of the 



phenocrysts. 



13- 



Glassy plagioclase 



phenocrysts 



{^itr. ) 



14. 



Opaque plagioclase 



phenocrysts 



(opac. ) 



15- 



Large phenocrysts 

 of olivine and 

 pyroxene, over 

 2 mm. (inagn.) 



16. 



Small phenocrysts 



of olivine and 



pyroxene, under 



2 mm. Pyroxene 



scanty and often 



absent (parv.) 



( 17. Vitr. 

 \ 18. Opac. 



{19. Magti. 

 20. Parv. 

 '21. Vitr. . 



22. Opac. 

 ! 23. Magn. 

 y 24. Parv. 



Species. 



Length 



of felspar 



lathes. 



•02- 

 •I- 



•2- 

 •3- 



"i mm. 

 •2 „ 

 "3 ., 

 ■5 ., 



Number of 

 specimens. 



/ Not repre- 

 \ sented. 



Not repre- 

 sented. 



