STUDIES OF VARIATION IN INSECTS 263 



to those of the other series. The frequencies of the variations 

 are as follows : 



Class A. With 12 spots (6 on each elytron) present and 

 separate (total 1,556 individuals). Subclass i (mode): 711 in- 

 dividuals; subclass 2: 493 individuals; subclass 3 : 116 indi- 

 viduals ; subclass 4 : 55 individuals ; new subclasses : various 

 other combinations of reduction, and enlargement of spots, 181 

 individuals. 



Class B. With some spots coalescing (total of 17 individ- 

 uals). Subclass 12 : 6 individuals ; subclass 14: i individual; 

 subclass 15: 4 individuals; subclass 16: i individual; new 

 subclasses : 2 individuals showing other combinations. 



Class C. Lacking some of the modal 12 spots (total of 116 

 individuals). Subclass 20: 16 individuals; subclass 21: 11 

 individuals ; subclass 24 : 24 individuals ; subclass 26 : 4 indi- 

 viduals ; subclass 38 : 24 individuals ; subclass 39 : 14 indi- 

 viduals ; subclass 46 : 5 individuals ; new subclasses : 18 indi- 

 viduals in several other combinations each represented by one 

 or two individuals. 



Class D. With more than the 12 modal spots (total 36 indi- 

 viduals). Subclass 49: 8 individuals; subclass 50: 17 indi- 

 viduals; subclass 51 : 11 individuals. 



Comparing now this 1902 series of 1,730 individuals with the 

 two series of 1901, the percentages of the various variation 

 classes are as follows: Class A: 87+ per cent, in series of 

 1,031 ; 90— per cent, in series of 751 ; 90— per cent, in series 

 of 1,730. Subclass I (the mode) : 52 per cent, in series of 1,031; 

 38.5 per cent, in series of 751 ; 41 per cent, in series of 1,730. 

 Class B: 2.5 per cent, in series of 1,031 individuals; 1.6 per 

 cent, in series of 751 individuals ; i— per cent, in series of 1,730 

 individuals. Class C : 6.9 per cent, in series of 1.031 indi- 

 viduals ; 7.5 per cent, in series of 751 individuals ; 6.8 per cent, 

 in series of 1,730 individuals. Class D : 3.7 per cent, in series 

 of 1,031 individuals; 3 per cent, in series of 751 individuals; 

 2.5 per cent, in series of 1,730 individuals. 



Thus there is obvious a close correspondence in frequencies 

 of variation classes in the three series except in one conspicuous 

 subclass, that of the mode. The mode class agrees well but 



