76 THE CASE OF PAPILIO POLYTES [ch. 



for many years they were regarded as distinct species, 

 and given definite specific names. To Wallace belongs 

 the credit of shewing that these three forms of female 

 are all to be regarded as wives of the same type of 

 male^. He shewed that there were no males corre- 

 sponding to two of the females ; also that the same one 

 male form was always to be found wherever any of the 

 females occurred. As the result of breeding experi- 

 ments in more recent years Wallace's conclusions have 

 been shewn to be perfectly sound. 



The male of polytes (PI. V, fig. 1) is a handsome 

 blackish insect with a wing expanse of about four 

 inches. With the exception of some yellowish-white 

 spots along their outer margin the fore wings are entirely 

 dark. Similar spots occur along the margin of the hind 

 wing also, while across the middle runs a series of six 

 yellowish-white patches producing the appearance of 

 a broad light band. The thorax and abdomen are full 

 black, though the black of the head is relieved by a few 

 lighter yellowish scales. The under surface is much 

 like the upper, the chief difference being a series of 

 small and slightly reddish lunules running outside the 

 light band near the margin of the hind wing (PI. V, 

 fig. 1 a). In some specimens these markings are almost 

 absent. One form of female is almost exactly like 

 the male (PI. V, fig. 2), the one slight difference being 

 that the lunules on the under surface of the hind wing 

 are generally a trifle larger. For brevity she may 

 be called the M form. The second form of female 



^ Trans. Linn. Soc. vol. 24, 1866. 



