Pyrite, [452].

Pyrolusite, [456].

Pyroxenes, [458].

Quartz, [458].

Quartzite, [466].

Quebradas, [75].

Rabot, C., cited, [424].

Radiating glaciers, [383], [386].

Raft lakes, [417], [418].

Rafts, log, in Red River, [418].