wind when thermally different strata become mixed, cf. 

 Epilimnion. 



Oviparous 



Refers to an animal that lays eggs in which embryos 

 show little or no development, e. g., most fishes, cf. Vivi- 

 parous, Ovoviparous. 



Ovipositer 



A specialized structure in insects for depositing eggs. 



Ovoviparous 



Refers to an animal that keeps ova or eggs within the 

 body until they are ready to hatch, requiring internal fer- 

 tilization, as in birds, cf. Oviparous, Viviparous. 



Ovule 



The structure within the Ovary of a flower that after 

 Fertilization of the egg within it develops into a seed. 



Ovum 



A female Gamete (q. v.) or egg. 



Oxbow Lake 



A more or less semicircular lake or pond formed when 

 a meander of a river is separated from the main stream. 



Oxidation-reduction Potential 



The potential of a given material, in comparison with 

 other materials, to release electrons (oxidation), or to receive 

 electrons (reduction); symbolized by E h . syn. Redox poten- 

 tial. 



Oxylophyte 



See Acidophilous. 



Oxyphilous 



See Acidophilous. 



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