the Mediterranean Ocean, characterized by hot, dry summers 

 and cool, rainy winters. 



Medium-height Grass 



In the classification of grasses according to height, the 

 class that ranges from 2 to 5 feet in height, includes Mid- 

 grasses (q. v.). cf. Highgrass, Shortgrass. 



Megagea Realm 



One of the three classes of the earth's fauna, which 

 includes the Ethiopian, Oriental, Palearctic, and Nearctic 

 regions, cf. Neogea, Notogea. 



Megaphanerophyte 



A group of plants in Raunkiaer's life-form classification 

 which includes trees, lianas, and epiphytes over 30 meters 

 high. 



Megaphyll 



See Leaf-size classes. 



Megaspore 



The larger of two kinds of spores produced by plants such 

 as Selaginella and the Spermatophytes (q. v.). cf. Microstore. 



Megatherm 



An organism that requires continuously high tempera- 

 tures, and according to some usage abundant moisture, e.g. 

 sugarcane, cf. Mesotherm, Microtherm, Hekisto therm. 



Nleiosis 



The two successive divisions of the nucleus in which the 

 Chromosome number is halved, from the Diploid (q. v.) to 

 the Haploid (q. v.) number. 



Melanism 



The unusual development of a dark pigment in an 



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