Snowfence 



A fence of slats and wire or other material used to inter- 

 cept drifting snow. 



Snowfield 



An area or mass of snow that remains throughout the 

 summer. 



Snowflush 



A deposit of soil material accumulated in a mass of snow 

 following melting of the snow. 



Snow Line 



A line marking the lower limit of perpetual snow. 



Snow-Patch 



An area in which snow melts late in the year and where 

 Snowflush forms and vegetation is characteristic of such a site 

 or is lacking. 



Snow Sample 



A core taken in an accumulation of snow from which the 

 depth and density of the snow may be determined. 



Snow Survey 



A series of measurements of the depth and density of 

 the accumulation of snow, usually for the purpose of deter- 

 mining the amount of water that is stored in the form of 

 snow on a drainage basin, as a means of forecasting the later 

 run-off. 



Sociability 



The distribution of organisms in relation to one another 

 as individuals or as groups within a community. J. Braun- 

 Blanquet recognizes five classes of sociability, ranging from 

 isolated individuals to dense masses. 



Social Behaviour 



The activity of an animal caused by another animal or 



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