GENETIC EVIDENCE FOR DIPLOID MALES. 445 



irregular dominance. One of these normal black males was mated 

 to three orange females by each of which he produced a single 

 daughter. 



From one cross there were produced 30 orange males and in 

 vial b a single black-eyed female of small size and with asym- 

 metry of ventral abdominal sclerites. She produced only one 

 larva which died. Whether she posessed D or d is not known. 

 Her morphological abnormality and near sterility are comparable 

 with such conditions in daughters of biparental males transmitting 

 only dominant traits. 



From another cross there were produced 92 orange males and 

 in vial c a single orange female. She developed from a naked 

 pupa and had asymmetrical sternites. She appeared normal in 

 internal morphology and histology and produced 3 orange sons, I 

 normal and 2 defective. Since her mother was of normal orange 

 stock the occurrence of these indicates that she had received d 

 from her father. Like many daughters of other biparental males 

 she was of abnormal appearance, but unlike them she was some- 

 what fertile. 



From the third cross there were produced 136 orange males 

 and, in vial a, a single orange female. This female was normal 

 in appearance and produced 71 offspring, males 13 normal, 16 

 defective, and females 23 normal and 19 defective. The defec- 

 tives were due to the fact that this female's mother had d. Nor- 

 mal venation was isolated in later generations. 



This biparental male had, therefore, in addition to black-bearing 

 spermatozoa, two types of orange, od, the maternal combination, 

 and oD, a recombination type. He is the only male found which 

 breeds like a heterozygote. He and his daughters are not included 

 in the following summary. 



Of the 186 dominant daughters of biparental males only 121 

 were sufficiently normal to test. Most of these laid eggs which 

 failed to hatch. Some lived for several days, stung the host 

 caterpillars but laid no eggs. One gave a normal black male 

 which proved sterile ; one produced a black-eyed female pupa which 

 died in the cocoon ; one gave a morbid larva which died young and 

 an abnormal female pupa with black eyes found dead in the cocoon ; 

 and another an abnormal pupa of uncertain eye-color and sex, and 

 a fifth five larvse which died and a female pupa of uncertain eye- 



