No. IV. ArPENDIX. 373 



I. — The Granitic and Granitoid Hocks. 



These rocks form a considerable part of North Green- 

 land, on the east side of Baffin's Bay, and constitute the 

 rock of the country at the east side of the island of 

 North Devon, which forms a portion of the coast-line 

 of the west of Baffin's Bay, and the north side of the 

 entrance into Lancaster Sound. 



1. WTiale Fish Islands, lat. 69° N., are composed of a 

 very fine-grained, flaggy, black mica schist, composed 

 of black mica in very small plales, occasionally putting 

 on a hornblendic lustre, and minute grains of quartz 

 interstratifled with the mica. The softer varieties are 

 cut by the natives into grissets and cooking utensils of 

 various shapes, some of which resemble the cambstones 

 found in Ireland, which are made from a kind of pot- 

 stone, abundant in parts of the County Donegal. 



2. Upernavik, lat. 72° N., Greenland. — This district 

 is famous for the occurrence of large quantities of plum- 

 bago, which is found in a metamorphic rock of the 

 following character. Fine-grained, amorphous, grani- 

 toid rock, composed of minute particles of grey quartz ; 

 a honey-coloured felspar of waxy lustre, of unknown 

 composition; minute particles of red semitransparent 

 garnet, of conchoidal fracture ; and small particles, with 

 occasional large nests, of plumbago. The plumbago 

 occurs both amorphous, and in long acicular crystals. 

 Sometimes the rock becomes of coarser texture and 

 more crystalline, and the yellow colour of the felspar 

 gives place to a greenish tinge ; and it sometimes also 

 becomes a felspar of perfect cleavage, semitransparent, 

 and white. The dodecahedral crystals of garnet reach 

 the diameter of one inch. 



The general character of the rocks near Upernavik 

 is different from that of the rock in which the plumbago 

 is found; they consist of a fine-grained black mica schist, 



