232 The Inheritance of Wing Colour in Lepidoptera 



Figs. 5, 6, 7 and 8 show the curves given by four separate families in 

 : which the offspring were numerous enough to be treated by 4ihemselves. 

 The essential features are much the same as in the last case. In family 

 '17 C (Fig. 5) the BR individuals are indeed slightly darker than the 

 % parent (hybrid) whereas the RR insects are nearly all paler than the 

 </ parent (lutea) which was very deep [43 : 4-9]. Two separate curves 

 have been added to this figure to indicate the orange values of the 

 hind wings, and the black values of the fore wings (see p. 218). 



1 2 3 4| 6 Colour-units 



[0-7: 0-5] [4-3: 4-9] 



Colour-value of Colour- value of 



hybrid parent , lutea parent 



Fig. 5. (Cf. Fig. 18.) Curve showing the frequency distribution of the 

 orange and yellow colour- values of family '17 C, hitea x hybrid 

 {lutea X gross.). 



The orange colour of the hind wings is also shown by means of a dot-and- 

 dash line. The small quantities of black which occur so irregularly 

 in the fore wings are shown by means of a thin continuous line. 



Family '16 E (see Fig. 6) shows a somewhat similar curve; the 

 yellow (f parent [2*9 : 21] was not quite so dark as in the last figure, 

 and the J parent unfortunately was lost. However a record exists 

 saying that it was rather deeply coloured for a hybrid: the orange 

 colour-value being probably not less than 1*7. The result seems to be 

 a certain increase in the number of yellows. The double maximum 



