heads of many Composites. (2) The outer layers of cells of 

 grains removed during threshing. 



Chalk 



A gray or white form of limestone composed mostly of 

 the remains of small marine organisms, with a very high 

 content of calcium carbonate. 



Chamaephyte 



One of the classes of Raunkiaer's life-forms, consisting 

 of plants whose Perennating buds are located between the 

 surface of the ground and a height of 10 inches (25 cm.). 



Chaparral 



Low and often dense scrub vegetation characterized by 

 shrubs or dwarf trees with mostly evergreen and often hard 

 leaves such as oaks and buckbrush, cf. Maquis. 



Character 



An attribute or property of an organism, functional or 

 structural, modifiable by environmental conditions within 

 genetically determined limits. 



Character (Characteristic) Species 



The species in classes 3, 4, and 5 of Braun-Blanquet's 

 fidelity classification. Class 5 includes species occurring ex- 

 clusively or almost so in a particular kind of plant com- 

 munity; class 4 contains species that show a strong preference 

 for one kind of community but occurs sparingly in others; 

 class 3 contains species that often occur in several kinds of 

 communities but the optimum growth is found in only one 

 kind. cf. Fidelity. 



Characteristic Species-combination 



A group of species in a community-type, which comprises 

 the Character species and other species that have a Constancy 

 rating above 80 per cent (varies with authors from 60 to 90 

 per cent). 



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