THE GENETICS OF HABROBRACON JUGLANDIS ASHMEAD 



ity of cases they lack pigment. Dahlia and ma- 

 roon form a double recessive which is but 

 slightly different from either single type. 

 The lightening influence of one mutant on 

 another is not necessarily correlated with in- 

 tensity of its color. For example, maroon is 

 darker than dahlia, but when combined with car- 

 rot it gives white, whereas dahlia-carrot is a 

 somewhat lightened carrot ( A. R. V/hiting, 1934). 

 Mutations for eye size and shape have not 

 been as numerous as have those for eye color. 



KIDNEY, k (eyes). A mutation to kidney eye 

 shape was found on August 18, 1930, and was de- 

 scribed by P. W. Whiting (1932a). The mutant 

 appeared in a male with compound eyes lacking 

 with the exception of a very minute one on the 

 right side. Ocelli were of approximately nor- 

 mal size. The mother had been X-rayed with a 

 dosage of 2600 R units. When the wasps are 

 bred at 30° C, compound eyes and ocelli are 

 reduced in size and elongated dorso-ventrally , 

 some of them kidney shaped. The majority of 

 specimens are inviable, many dying in cocoons 

 as elongate pupae often with small heads. At 

 lower temperature, 25° C, for example, they 

 are of excellent viability and both sexes are 

 fertile. 



W. F. Dunning (1931) obtained two mutant 

 types, "small" and its allele "extreme small." 

 These have proved allelic with kidney. 



SMALL-EYES, k^ (eyes), and EXTREME-SMALL, k® 

 (eyes). These alleles are of normal viability 

 and fertility. A study has been made of domi- 

 nance in the kidney-extreme-small compound fe- 



50 



