128 



HEREDITY AND SEX 



tion, in the way that the upholders of the theory of 

 mimicry would lead us to suppose." 



After considering the difficulties that the theory of 

 mimicry has to contend with, Punnett points out that 

 dimorphic and polymorphic species are not uncommon 

 in butterflies, and that in many of these cases there can 

 be httle or no question of mimicry having anything 



Fig. 65. — Papilio turnus ; female (above) and male (below), and the variety 

 P. turnus glaucus (above, right) which appears only in the female. 



to do with the matter. It is well known that in Lepidop- 

 tera the modified form commonly belongs to the female 

 sex. In one case (Abraxas grossulariata) it is known 

 that the aberrant female type appears sporadically, as a 

 sport, and follows Mendel's law of segregation. Punnett 

 shows how the recurrence of the single type of male and 

 the three types of females of polytes may also be ac- 

 counted for by the recognised methods of Mendelian in- 

 heritance. He points out that by the assumption that 



