Vernal 



Refers to spring, cf. Aspection. 



Vernalization 



The process of hastening the flowering phase of plants 

 by subjecting young seedlings or other parts to low tempera- 

 ture, less commonly to a high temperature. 



Versant 



The general slope of a mountain range or a landscape. 



Vertebrate 



An animal in the subphylum Vertebrata, phylum Chor- 

 data, e.g., mammals, fishes, reptiles, birds. 



Vesperal 



Refers to evening time. cf. Crepuscular. 



Vessel 



A series of cells forming a tube-like structure in the 

 Xylem (q. v.) of plants, conducts water and substances in 

 solution. 



Vestigial 



Refers to a structure, function, or behavioural act of an 

 organism that has so decreased in importance during the 

 course of evolution that only a trace remains, e.g., the vermi- 

 form appendix in man. cf. Primitive. 



Viability 



The capability of a seed, spore, egg, or other organ of a 

 plant or animal to continue or resume growth when it is 

 exposed to favorable environmental conditions, cf. Dormancy. 



Viable 



Refers to the state of being alive, cf. Viability. 



Vicariad (Vicarious Species) 



One of a pair of closely related species, variety, or other 

 Taxon that replace each other geographically. 



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