NOTES ON ANTARCTIC ROCKS. 469 
or less incoherent, some oolitic, some in the condition of marble. 
Besides these are the fragments of hard yellowish magnesian 
limestone with Gyroporella, probably Triassic, the Paleozoic (‘) 
greyish-white limestones of the South Orkneys, fragments of 
various sandstones, arkose, quartzites, and clay shales. 
(c) Metamorphic rocks—These appear to be abundantly repre- 
sented and comprise :—gneisses, some hornblendic, containing 
zircon, microcline, sphene, apatite, rutile, tourmaline etc., mica- 
schists with tourmaline, microcline, sphene and epidote ; sericite 
quartz-schists, epidotic quartz-schists rich in rutile, argillaceous 
schist with crystals of biotite and garnet, and numerous particles 
of graphite, phyllite schists and tale schists. 
With regard to the volcanic zone of Antarctica the following is 
a list of the volcanoes at present known to us :— 
1. Balleny Island ... Dormant (?)... ... 12,000 feet high, 
2. Buckle Island ...Active (7)... ... small. 
3, Mount Sabine —_... Extinct 49 gee ... 9,500 feet, 
4. Cone observed by Borchgrevink near Mt. 
Sabine apparently recently in eruption, 
Active (). 
5. Mount Herschell ...Extinct ... ... 14,000 feet (?) ,, 
6. Mount Melbourne... Extinct(? large crater). 
7. Mount Erebus _... Active is ... 12,367 feet (?) 5, 
8. Mount Terror ...Extinct (1) ... ... 10,884 feet 5 
9. Mount Haddington Extinct (?) ... --» 7,050 feet 
10. Cockburn Island ...Extinct (7)... +» 2750 feet 55 
11. Paulet Island CO Oe FAs ihe 750 feet 5 
12. Etna Island ... Extinct (7) ... soe 1,300 £006... ...44 
13, Bridgman Island ... Active cone ... 400 feet (?) », 
i, Apsland Island... Extinct crater.. 
15. Astrolabe Island ... Extinct crater ... 1,000 feet (?) » 
16. Deception Island—Large partly submerged 
crater with numerous fumaroles, dormant (?) 800 — 1,800ft. », 
ui. Christensen Volcano Active... ..- Small. 
18. Sarsee Voleano ... Active... ay 
