Merriam's Life Zones 



A series of belts or Life zones (q. v.) based originally on 

 criteria of temperature according to C. Hart Merriam. See 

 Alleghanian, Carolinian, Hudsonian, Sonoran, Transitional, 

 Tropical Life zones. 



Mesa 



A flat or nearly flat table land with steep sides. 



Mesarch 



Refers to a successional series that begins in a moderately 

 moist habitat, cf. Hydrarch, Xerarch. 



Meseta 



The greatly eroded, broad plateau in the interior part 

 of Spain, crossed by a few mountain ridges. 



Mesic 



Refers to environmental conditions that are medium in 

 moisture supply, cf. Mesophytic, Hygric, Xeric. 



Mesolimnion 



See Thermocline. 



Mesophanerophyte 



One of the groups of plants in Raunkiaer's life form 

 classification, consisting of trees, lianas, and epiphytes, 8 to 

 30 meters tall. 



Mesophyll 



The palisade and sponge cells between the upper and 

 lower epidermises in a leaf. 



Mesophyte 



A plant that grows in environmental conditions that are 

 medium in moisture conditions, e. g., corn. 



Mesophytic 



Refers to a Mesophyte. 



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