Ethiopian Region 



The faunal region in the realm Megagea (Arctogea); it 

 includes all of Africa except the northern corner and part of 

 southern Arabia. 



Ethnobotany 



The study of the use of plants by any race or group of 

 people, cf. Paleobotany, Paleontology. 



Ethnology 



The study of the distribution and characteristics of the 

 divisions of mankind. 



Ethology 



The comparative study of the Behaviour of animals. 



Etiolation 



The development of a plant grown without light, result- 

 ing in the loss of chlorophyll, a weak elongated stem, and 

 abnormal leaves. 



Etiology 



The study of the causes of diseases. 



Eucoen 



See Index species. 



Eugenics 



The study of the improvement of the genetic constitu- 

 tion of a population or species, especially the human race. 



Eulittoral 



The shoreward part of the Benthic zone in lakes and 

 oceans; the landward part of the littoral zone, including all 

 of the inter tidal region, cf. Littoral. 



Euphotic Zone 



The uppermost portion of a body of water which re- 

 ceives sufficient light for Photosynthesis, cf. Aphotic, Dis- 

 photic, Photic zones. 



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