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GENERAL BIOLOGY 



bars of the wings of a night hawk, or the golden shafts of the 

 flicker, or the white side spots of a junco's tail, or the white 

 rump of a rabbit, exposed only when the tail is lowered in 

 running, or the brilliant reds and blacks of the underwing 

 moths, etc., etc. These are suddenly flashed into view when 



FIG. 251. A carrion beetle (Necrophorus) ; colors dull 

 red and black. 



their possessor takes flight, and as suddenly tucked away 

 again on alighting. They have been called "recognition 

 marks" on the assumption that they enable a fleeing herd of 

 gregarious animals of one species to keep together or help 

 individuals to find one another more readily. But it seems 



