48 P. W. WHITING. 



The progeny from orange males derived from orange females 

 crossed with black males are summarized below. 



The inheritance is thus far seen to be quite in accordance with 

 expectation. 



The case must be mentioned of the occurrence of a single 

 orange male in a cross (237) involving only type stock. There 

 were produced 115 black males and 83 black females besides 

 this orange male. This was possibly a second mutant as it is 

 highly improbable that contamination of the culture could have 

 taken place. 



(d) The Occurrence of Anomalous Males. The cross of black 

 male by orange female remains to be considered. Black daughters 

 and orange sons are to be expected. Thirty-three such crosses 

 have been made and the results are summarized in Table I. 

 Eleven agree with expectation, giving 183 black females and 

 445 orange males. The other twenty-two, however, produced 

 in addition to 816 black females and 889 orange males, 57 black 

 males. 



It has been shown above that the sons of virgin orange females 

 have always been orange. These anomalous blacks must then 

 have derived their eye color from the sperm nucleus, and con- 

 sequently must have developed from fertilized eggs. 



Anomalous black males and some of their orange brothers 

 were tested by mating to orange females. Table II. shows the 

 results of these tests. Seven black males produced orange 

 daughters only, showing that although their eyes were paternal 

 in origin their gonads were from maternal nuclei. They are 

 therefore mosaics. One of these males, No. 2, was mated success- 

 fully to five orange females and sired in all 118 orange daughters. 



Five black males produced black daughters only and hence 

 their gonads as well as their eyes were of paternal tissue. One 

 of these, No. 8, was tested with two females. 



Eighteen orange males sired orange daughters only. These 

 males were therefore produced in regular manner from un- 

 fertilized eggs or, if sperm nuclei entered, they took no part in 

 the formation of eyes or gonads. 



One orange male, No. 17, produced 19 black daughters, thus 



