GENE MUTATIONS 



males as affected by temperat'ire differences 

 (Speicher, 1932b, lQ33a,b, 1934a, b). The eye 

 size of mutant-type wasps showing this charac- 

 ter is extremely variable, ranging from a total 

 lack of eyes to those which, though approaching, 

 never reach the normal size (F'ig. 4). The in- 

 dividual facets, when present, are of normal 

 shape and size, the variation occurring as a 

 decrease in the total number. The sizes of 

 right and left eyes vary somewhat independently 

 of each other. The ocelli are likewise affected 

 and are also extremely variable, ranging from 

 none at all to those apparently normal in size. 

 Although no actual measurements have been made, 

 it has been noted that the ocelli of any one 

 individual tend to be of the same size. Aside 

 from the modification of compound and simple 

 eyes no other external effect is manifest, 

 (Discarded) 



SMALL, sm (eyes). This mutant appeared in the 

 summer of 1934 in the offspring of an X-rayed 

 female (dosage about 4500 R units). This mu- 

 tant, in v;hich the compound eyes are much re- 

 duced in size, closely resembles small-eyes. 

 It was discarded soon after its appearance. 



EYELESS, el (eyes). W. F. Dunning (1931) re- 

 ported a mutation which she called eyeless, a 

 recessive mutant type in which the heads are 

 much malformed when the wasps are bred at 30° C. 

 with large lobes on either side. At lovirer tem- 

 peratures these lobes fail to appear. Rudi- 

 ments of compound eyes may be present, and the 

 wings tend to be somewhat wrinkled. Both sexes 

 are fertile, but females are somewhat weak. 



31 



