J. S. W. NUTTALL 123 



expected number of red chequers and more than the expected number 

 of blue chequers. The experiments having been for the present almost 

 suspended, the testing of the extracted colours is incomplete. As far 

 as this has been carried out, the anticipated results have been obtained. 



The blue chequers have proved to be homozygous for colour, some 

 being heterozygous for chequering ; the mealies homozygous for absence 

 of chequering, some giving rise to blues ; the blues have proved to be 

 homozygous for colour and absence of chequering. (See comments on 

 group 6 for occurrence of white in these extracted colours.) 



Group 2. The heterozygous composition of red chequers may be 

 expected to have a greater effect in this type of mating than in group 1 

 type. The blue chequers being homozygous, and probably the majority 

 of the red chequers heterozygous for colour, it follows that the observed 

 red chequer figure will be low and that for blue chequer high. It is 

 worthy of mention that the colour of red chequers bred from dissimilarly 

 coloured parents (red chequer and blue chequer, or red chequer and blue) 

 is, as a rule, richer than that of birds bred from two reds. This probably 

 accounts for the popular aversion to red chequer and red chequer mating. 

 Red chequer cock birds from red chequer x blue chequer almost in- 

 variably possess black ticks. I have not found an example of these black 

 ticks in hen birds ; brown ticks may however sometimes be met with. 



All the red chequered cocks which have come under my notice, 

 having one parent blue or blue chequered, present some degree of 

 ticking. A proportion of those from two red chequers and of those 

 from red chequer x mealy, are free fi'om ticks and do not appear to 

 develop any with age. On this may rest the possibility of separating 

 the homozygous and heterozygous red chequers of the male sex. 



Group 3. As, in this group, red may come from either parent, the 

 effect of the heterozygous composition of red chequer is modified and 

 the observed approaches closely to the estimated result. The extracted 

 blue chequers and blues have so far proved to be pure for colour. 



Group 4. The results obtained in this group and in group 3, 

 suggest that chequering depends on a single factor, and that it may 

 produce its full effect even when contributed by one parent. The 

 eleven blue chequers in this group were typical of the chequered type. 



Group 5. A correlation was observed between paleness of plumage 

 (ground colour especially) and light coloured beaks and claws in some 

 of the mealies in this group. Of the blues, however, two in particular 

 were exceptionally sound in colour with dark beaks and claws. Blues 



