H. Onslow 



t>L>9 



type siKKiiinens, coIIccIimI fnun varinns localities, Imvc 

 iiml in no insect <li<l the c(jlonr-viilue exceed |ll :0 

 great niajority wen* |0 7 : O'd] or less. 



l)een e 



:il. will 



xiuiiined, 



•rejL« the 



17 a "16 P 'ISC '14 a 

 '17 K. 16 T '15 P. '08-5.'' 

 '17 a '15 K. 08-20' 

 '17 6. ^5M. 



'I5Q. 



4 Colour-units 



[0-G:0-5] 

 Mean colour-value of 

 grossulariata parents 



[3-3: 2-8] 



Mean colour-value of 



lutea parents 



Fig. 2. 



(Cf. Fig. 15.) Curve showing frequency distribution of the orange and yellow 

 colour- values of the offspring from 14 pairings of hitea x grossulariata. 



All the families resulting from pairings of lutea x grossulariata are 

 small and have been combined in a single curve (see Fig. 15). The mean 

 orange value of the yellow parents was 3'3 or nearly six times as yellow 

 as the mean value of the type parents, which was 0*6. The frequency 

 distribution (Fig. 2) reaches a maximum at about 1*0, showing that the 

 factor for yellowness is not completely recessive, because the majority 

 of the offspring are more deeply coloured than their type parents. 

 However the orange colour represented by TO unit of orange is a very 

 pale cream, rather paler than insects Nos. 20 and 21, Plate IX. It 

 was found to make no difference in the offspring whether the male 

 parent was a grossulariata or a lutea, so the reciprocal matings have 

 been combined in one curve. They can be easily separated, however, 

 by reference to the pedigree and Table I. The curve though rather 

 narrow is not unlike an ordinary frequency distribution. The range of 



