Draw 



A natural depression or swale; a small natural drainage- 

 way. 



Drift (Geology) 



Material of any kind which is deposited in one area after 

 having been moved from another, most commonly used in 

 reference to glacial drift, the material deposited by glacial 

 action. Glacial drift includes Till (q. v.) and stratified out- 

 wash materials, cf. Loess, Boulder-clay, Drumlin. 



Drift Barrier 



An open structure constructed across a stream channel to 

 catch driftwood, such as a wire fence. 



Drift Fence 



A fence for the purpose of preventing livestock from 

 going from their regular range to another, often used in con- 

 nection with natural barriers. 



Drift, Genetic 



Random changes in the characteristics or attributes of 

 populations that are usually isolated, or in the frequencies 

 of certain genes, which cannot be attributed to selection, mu- 

 tation, or migration, cf. Natural selection. 



Drift Ice 



Portions of icebergs or ice-floes in the open sea outside 

 of the areas of pack-ice. 



Drill Seeding 



Sowing seeds with a drill usually in rows that are less 

 than one foot apart as in seeding grains, cf. Broadcast seed- 

 ing. 



Drip Point 



The long, attenuate tip of many leaves in the Rain 

 forest of the Tropics. 



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