39G APPEXDIX III 



that the specimens from Mount Betty and Scott's Nunatak consist 

 exclusively of granitic rocks and crystalline schists. There were 

 no specimens of sedimentary rocks which, by possibly containing 

 fossils, might have contributed to the determination of the age of 

 these mountains. Another thing that was immediately apparent 

 was the striking agreement that exists between the rocks from 

 these two places, lying so far apart. The distance from Mount Betty 

 to Scott's Nunatak is between seven and eight degrees of latitude. 



I have examined the specimens microscopically. 



From Mount Betty there are several specimens of white granite, 

 with dark and light mica; it has a great resemblance to the white 

 granites from Sogn, the Dovre district, and Nordland, in Norway. 

 There is one very beautiful specimen of shining white, fine-grained 

 granite aplite, with small, pale red garnets. These granites show 

 in their exterior no sign of pressure structure. The remaining 

 rocks from Mount Betty are gneissic granite, partly very rich in 

 dark mica, and gneiss (granitic schist); besides mica schist, with 

 veins of quartz. 



From Scott's Nunatak there are also several specimens of white 

 granite, very like those from Mount Betty. The remaining rocks 

 from here are richer in lime and iron, and show a series of gradual 

 transitions from micacious granite, through grano-diorite to quartz 

 diorite, with considerable quantities of dark mica and green horn- 

 blende. In one of the specimens the quantity of free quartz is so 

 small that the rock is almost a quartz-free diorite. The quartz 

 diorites are: some medium-grained, some coarse-grained (quartz- 

 diorite-pegmatite), with streaks of black mica. The schistose rocks 

 from Scott's Nunatak are streaked, and, in part, very fine-grained 

 quartz diorite schists. Mica schists do not occur among the speci- 

 mens from this mountain. 



Our knowledge of the geology of South Victoria Land is mainly 

 due to Scott's expedition of 1901-1904, with H. T. Fferrar as 

 geologist, and Shacklcton's expedition of 1907-08, with Professor 

 David and R. Priestley as geologists. According to the investiga- 



