250 



KELLOGG AND BELL 



Classes 



^Mi^mMm i±JSii±[tt# frrl f l-tijfeiiiaigit 



Fig. 40. Frequency polygon of the variation in width of the right fore wings 

 of 194 male black ants, collected at one time in one place; mean 27.02 microm- 

 eter units ; index of variability 1.14 ; coefficient of variation 4.22. 



Fig. 41. Frequency polygon of tlie variation in measurement C (sec fig. 34) 

 in left fore wings of 194 male black ants, collected at one time and in one place; 

 mean 13.34 micrometer units; index of variability, 1.119; coefficient of varia- 

 tion 8.4. 



