VARIATION AND MUTATION 



133 



answer by calling attention to Figs. 72, 73, and 74 and what 

 these variations signify. Note also Fig. 75, showing the 



FIG. 73. Diagram showing variations in elytral pattern of convergent ladybird, 

 Hippodamia convergens: 1-5, Variations by different reduction in number of spots 

 in the two elytra; 6-9, variations by conditions of spots. (After Kellogg and Bell.) 



variation in elvtral blotching to be found in a series of Individ- 



*J C.5 



uals of the California flower beetle, Diabrotica soror; see also 

 Fig. 76, showing the vari- 

 ations in the black and 

 yellow color pattern of the 

 abdomen of the common 

 yellow jacket (Vespa sp.); 

 and Fig. 77 showing the 

 variation in the pattern of 

 the prothorax in a series of 

 178 individuals of a common 

 California!! flower bug, all 

 these individuals collected 

 at one time by sweeping a 

 net over a few rods of alfalfa 

 and Baccharis on the campus 

 of Stanford University. 



FIG. 74. Diagram showing variations in 

 prothoracic pattern of the convergent 

 ladybird, Hippodamia convergens. (After 

 Kellogg and Bell.) 



These are all color and 

 pattern variations; but in- 

 sects show variations in structural parts as well. Fig. 78 shows 

 a common red-legged locust and one of its hind tibiae enlarged 

 10 



