Second Order of the Hypersthene-Augite Andesites.
Characters.—Felspar-lathes in flow-arrangement.
Formula.—Hypersth.-aug., matr., flu.
| Sub-order. | Section. | Genus. | Species. | Number of specimens. | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pyroxene of the groundmass. | Presence or absence of plagioclase phenocrysts. | Character of the phenocrysts. | Length of felspar lathes. | |||||||||||
| 4. Granular (gran.) | 7. Plagioclase phenocrysts (phen.) | 13. Glassy plagioclase phenocrysts (vitr.) | ·02-·1 mm. | 9 | ||||||||||
| ·1-·2 " | 2 | |||||||||||||
| 14. Opaque phenocrysts of plagioclase (opac.) | Not represented. | |||||||||||||
| 8. No plagioclase phenocrysts (non-phen.) | 15. Large phenocrysts of pyroxene, over 2 mm. (magn.) | Not represented. | ||||||||||||
| 16. Small pyroxene phenocrysts, under 2 mm., or none (parv.) | Not represented. | |||||||||||||
| 5. Prismatic (prism.) | 9. Phen. | 17. Vitr. | ·02-·1 mm. | 2 | ||||||||||
| 18. Opac. | ·02-·1 mm. | 4 | ||||||||||||
| 10. Non-phen. | 19. Magn. | Not represented. | ||||||||||||
| 20. Parv. | ·02-·1 mm. | 4 | ||||||||||||
| ·1-·2 " | 2 | |||||||||||||
| 6. Ophitic (oph.) | 21 | Not represented. | ||||||||||||
| 22 | ||||||||||||||
| 23 | ||||||||||||||
| 24 | ||||||||||||||