First Order of the Hypersthene-Augite Andesites.
Characters.—Felspar-lathes not in flow-arrangement.
Formula.—Hypersth.-aug., matr., non-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. | |||||||||||
| 1. Granular (gran.) | 1. Plagioclase phenocrysts (phen.) | 1. Glassy plagioclase phenocrysts (vitr.) | ·02-·1 mm. | 12 | ||||||||||
| ·1-·2 " | 4 | |||||||||||||
| 2. Opaque phenocrysts of plagioclase (opac.) | Not represented. | |||||||||||||
| 2. No plagioclase phenocrysts (non phen.) | 3. Large phenocrysts of pyroxene, over 2 mm. (magn.) | Not represented. | ||||||||||||
| 4. Small pyroxene phenocrysts, under 2 mm., or none (parv.) | ·3-·5 mm. | 1 | ||||||||||||
| 2. Prismatic (prism.) | 3. Phen. | 5. Vitr. | ·02-·1 mm. | 2 | ||||||||||
| ·1-·2 " | 2 | |||||||||||||
| 6. Opac. | ·02-·1 mm. | 1 | ||||||||||||
| ·1-·2 " | 1 | |||||||||||||
| 4. Non phen. | 7. Magn. | Not represented. | ||||||||||||
| 8. Parv. | ||||||||||||||
| 3. Ophitic (oph.) | 9 | Not represented. | ||||||||||||
| 10 | ||||||||||||||
| 11 | ||||||||||||||
| 12 | ||||||||||||||