1/ P Y ^^^ tour -digit numberi m the column on the left give the latitude and longitude of the 

 '^ ^ ' loutheatt corner of each one degree-quadrar>gle. Eoch one-degree quodror^gle a divided 

 into 30-minute quadronglei, numbered as m the diagram to the right. The columns of these tables 

 give: A- minimum (emperalure, B-mommum temperature, C- number of years, D ■ number of days. 



DEPTH ZONE 



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