- 625 - 
t. Structural 
sediments 
rtion 
sandy, 
ly, stony 
plant 
Stellaria, Papaver, Saxifraga rivularis 
Cochlearia (S) 
Phypsia (R) 
Site No. 3 
Location: Melville Island (Air photo no.: A-16763-160) 
Dimensions: (maximum height above ground): 3’ 
Substrate: 
tions, 
1:63,000 
Upper substrate texture: sandy tilt 
Lower substrate texture: sandy 
Vegetation cover (%) 
Upper portion: unvegetated 
Lower portion: 5-15% plant cover 
Phytosociologic composition: 
Salix (D) 
Dryas (D) 
Moss sp. (S) 
Lichens (R) 
Site No. 4 
aga 
Location: Vassey Hamilton Island (Air photo no.: A-16764-54) 
Dimensions (maximum height above ground): 3-4’ 
Substrate: 
Upper substrate texture: clay-silt 
Lower substrate texture: gravel-clay 
Vegetation cover (%) 
Upper portion: unvegetated 
Lower portion: unvegetated 
A closer examination of sites revealed considerable simil 
arities in morphology, substrate texture, percentage of vegetation cover 
and some dissimilarities in phytosociologic composition on Melville 
Island. Similarity was also found in the distribution pattern of ice- 
pushed ridges throughout all sites. Single and multiple features with 
characteristically continuous and discontinuous patterns were common on 
both islands. 
Striking dissimilarities were apparent between ridges of 
Melville and Vassey Hamilton Islands in substrate texture, vegetation 
cover and phytosociologic composition. Most of the ridges had some 
or partial vegetation cover on Melville Island, whereas none of the 
ridges seemed to support any plant life on Vassey Hamilton Island. 
The reason for this may be due to specific local conditions, since 
the environment on Vassey Hamilton Island does not seem to favour plant 
growth at all. 
It is evident that the unconsolidated sediment of the upper 
ridge portions is relatively unfavourable for supporting a permanent 
vegetation cover. As a consequence, the upper part of the ridge surface