258 The Inheritance of Wing Colour in Lepidoptera 



Nos. 1, 7, 59 and 60 were very kindly given to me by the Kev. G. H. Eaynor, all the 

 other specimens were bred during the course of the experiments. 



PLATE X. 



1 and 2 were sketched with a Zeiss AA objective and ocular 5 giving a magnification 

 of about 200 diameters. 



3, 4 and 5 were drawn with the camera and a Leitz 1/20 inch oil immersion objective 

 and ocular 9, giving a magnification of about 1360 diameters. 



1. Portion of fore wing of var. iochalca (see Plate IX, No. 60) showing the way in which 



the melanic pigment is diffused throughout the scales. The base of the scales contains 

 most pigment but the effect is masked by the pale overlapping tips of those in the 

 preceding row. There are a few grey scales, but not sufficient to modify the colour 

 appreciably. 



2. Portion of the fore wing (near the costa) of var. nigrosparsata with yellow, not white, 



ground (as in Plate IX, No. 29) showing the way the melanic pigment is concentrated 

 in certain scales. The tips of the melanic scales usually contain more pigment than 

 the base, and further the yellow scales are almost devoid of black, which gives the 

 insect a faintly mottled appearance. 



3. 4, and 5. Unstained sections of the scales, about 2 to 3/a thick, of var. lutea from 



specimens of varying depths of colour, showing the way in which the yellow pigment 

 is diffused throughout the chitin of the walls of the scale. Even in the deepest 

 yellow insect (3) there is no granular pigment. 



