PLATE XXXVIII 



Fig. i. Metamorphosed Gabbro (foliated), Bertha Island, x 25 diam. 

 Showing augite, hornblende and biotite with a diablastic intergrowth of 

 augite and labradorite embaying a hornblende crystal (centre) ; felspar in 

 part granulitic. (No. 2.) 



Fig. 2. Metamorphosed Gabbro, Bertha Island, x 25 diam. Showing horn- 

 blende embayed by an augite-plagioclase diablastic intergrowth. Above 

 right, hypersthene, below left, augite. (No. 4.) 



Fig. 3. Metamorphosed Gabbro (garnetiferous), Bertha Island, x 25 diam. 

 Augite (top and centre) with coronae of garnet with intervening ring of 

 quartz. Iron ores in part surrounded by garnet, pyroxene and felspar in 

 part granulitic. (No. 4.) 



Fig. 4. Metamorphosed Gabbro (garnetiferous), Bertha Island, x 25 diam. 

 Hypersthene (centre) and augite (top left) with garnet coronae and inter- 

 vening ring of quartz; a large garnet with fine vermicular augite (right 

 centre). (No. 4.) 



Figs. 2, 3 and 4 have been photographed from the one rock specimen and 

 show the change of mineral composition as the contact of coarse hornblende- 

 plagioclase rock is approached. (Cf. text p. 182.) 



