Second Order of the Augite-Andesites.
Characters.—Felspar-lathes of the groundmass in flow-arrangement.
Formula.—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 and prisms. | |||||||||
| 4. Granular (gran.) | 7. Plagioclase phenocrysts (phen.) | 13. Glassy plagioclase phenocrysts (vitr.) | ·02-·1 mm. | 10 | ||||||||
| ·1-·2 " | 10 | |||||||||||
| ·2-·3 " | 4 | |||||||||||
| ·3-·5 " | 1 | |||||||||||
| 14. Opaque phenocrysts of plagioclase (opac.) | ·02-·1 mm. | 2 | ||||||||||
| 8. No (or very few and small) plagioclase phenocrysts (non-phen.) | 15. Large phenocrysts of augite, over 2 mm. (magn.) | Not represented. | ||||||||||
| 16. Small augite phenocrysts, under 2 mm. or none (parv.) | ·02-·1 mm. | 12 | ||||||||||
| ·1-·2 " | 14 | |||||||||||
| ·2-·3 " | 4 | |||||||||||
| ·3-·5 " | 3 | |||||||||||
| 5. Prismatic (prism.) | 9. Phen. | 17. Vitr. | ·1-·2 mm. | 1 | ||||||||
| 18. Opac. | Not represented. | |||||||||||
| 10. Non-phen. | 19. Magn. | Not represented. | ||||||||||
| 20. Parv. | ·02-·1 mm. | 4 | ||||||||||
| ·1-·2 " | 4 | |||||||||||
| 6. Ophitic (oph.) | 11. Phen. | 21. Vitr. | ·1-·2 mm. | 3 | ||||||||
| 22. Opac. | Not represented. | |||||||||||
| 12. Non-phen. | 23. Magn. | Not represented. | ||||||||||
| 24. Parv. | ||||||||||||