248 



A NATURALIST IN THE PACIFIC 



CHAP. 



Second Order of the Hypersthene-Augite Andesites. 



Characters. — Felspar-lathes in flow-arrangement. 



Formula. — Hypersth.-aug., matr., flu. 



Sub-order. 



Pyroxene 



of the 



groundmass. 



4- 



Granular 



(gran.) 



. 5- 

 Prismatic 

 (prism. ) 



6. 



Ophitic 



(oph.) 



Section. 



Presence or 

 absence of plagio- 

 clase phenocrysts. 



Plj^oclase 



phenocrysts 



(phen.) 



No plagioclase 

 phenocrysts 

 {non-phen.) 



9. Phen. 



10. Non-phen. 



Genus. 



Character 



of the 



phenocrysts. 



^3- . 

 Glassy plagioclase 

 phenocrysts 

 {vitr. ) 



14. 

 Opaque phenocrysts 

 of plagioclase 

 ^{opac.) 



{ ^5- 



Large phenocrysts 



of pyroxene, 

 over 2 mm. {i/iagn.) 



16. 



Small pyroxene 

 , phenocrysts, under 

 2 mm., or none 

 (parv.) 



Species. 



Length 



of felspar 



lathes. 



•02- 

 •I- 



•I mm. 

 •2 „ 



Number of 

 specimens. 



Not repre- 

 sented. 



Not repre- 

 sented. 



Not repre- 

 sented. 



Not repre- 

 sented. 



4 

 2 



Not repre- 

 sented. 



Third Order of the Hypersthene-Augite Andesites. 



Characters. — Felspars of the groundmass short and stout 



(orthophyric). 



Formula. — Hypersth.-aug., matr., orth. 

 Remarks. — The same classification is to be employed here as in 

 the case of the two previous orders, but as the rocks in my collec- 

 tion that belong to this order are not numerous (nine sections), it 

 will be sufficient to refer to the general remarks on the order 

 on p. 290. 



