212 bulletin: museum of comparative zoology. 



"While this glaciation has given a monotonous though not unpleasiug 

 character to the plateau, the headlands and islands of the coast exhibit 

 in detail a great variety of form. Sea-cliffs, benches, sea-chasms, fretted 

 ledges, beaches, gravel-bars, spits, and narrow coastal plains, all belong- 

 ing to the zone of postglacial emergence, add much to the scenic quality 

 and interest of a voyage along the coast. In this rugged soilless belt, 

 it is literally true that he who runs may read, and if he be a student of 

 geological processes, will find perpetual instruction from the coastal 

 views. 



The Geology. — South of Hamilton Inlet, the bed-rock seems to be- 

 long entirely to the crystalline complex (Plate 11). Assizes Island and 

 the mainland at the mouth of the St. Charles River, are underlain by 

 greatly contorted biotite and hornblende gneisses, biotite schists and 

 amphibolites ; quartz and pegmatite veins occur in large numbers. 

 Similar rocks were found at St. Francis Harbor on Granby Island. 

 The geology is further much complicated by the frequent occurrence 

 of large areas of massive and gneissoid granites and diorites and by an 

 equally persistent appearance of trap-dikes. The coarse gneissoid granite 

 of Great Caribou Island on the south side of St. Lewis Sound, was re- 

 marked for its development of ilmenite in anhedrons from one eighth to 

 one half an inch in diameter. The mineral showed a perfect develop- 

 ment of the octahedral parting which was again seen in the ilmenite 

 crystals an inch in diameter that are plentifully distributed in a vein of 

 graphic granite at Rogue's Roost, Seal Island. This vein is twelve feet 

 in average width and is beautifully exposed for some three hundred feet 

 of length. Seal Island is chiefly composed of coarse hornblende granite 

 cutting coarse diorite and is itself cut by pegmatites, fine-grained aplites 

 and numerous wide dikes of hornblende biotite diorite. 



Drift-ice prevented our anchoring in Domino Harbor and thus I had no 

 opportunity of seeing in its classic locality the " Domino Gneiss " of 

 Lieber, 1 nor the quartzitic rock described by Packard 2 and interpreted 

 by Bell 8 as representing a remnant of the Huronian in eastern Labrador. 

 In a private communication to the writer, Packard states that he is 

 inclined to agree with Bell that the latter rock is in reality an arkose. 

 At Pottle's Cove, West Bay, which Packard's map places in the zone of 

 the Domino Gneiss, a peculiar and striking rock-type has large develop- 

 ment. It is a medium-grained to fine-grained gneiss weathering under 



1 0. M. Lieber, Rep. U. S. Coast and Geodetic Survey, 1860, p. 402. 



2 A. S. Packard, Jr., The Labrador Coast, 1891, p. 286. 



3 R. Bell, Scot, Geog. Mag. 1895, Vol. XL, p. 349. 



