96 P. W. WHITING AND ANNA R. WHITING. 



normal. Mesosternum was yellow on right side, sooty on left. 

 Sooty is very variable but asymmetry of this trait rarely occurs. 

 Moreover, since the eyes were mosaic for orange and the mother 

 was heterozygous for sooty, this asymmetry may be taken as 

 representing true mosaicism. Vein r 4 was absent from the left 

 wing, present in the right. No significance can be attached to 

 this since the trait is commonly asymmetrical. 



Freak 185 was crossed to females of orange L. stocks, 3, 5, 

 and 10. There were produced orange males 518, of which 61 

 graded to sooty, and orange females, 245 or which 23 graded to 

 sooty. These orange females indicate that the mosaic trans- 

 mitted only orange. 



In order to determine whether he transmitted sooty and 

 defective, daughters were tested by breeding. From nineteen 

 daughters of stock 3 (od II95 S n D x ) females there were produced 

 orange males, 136 of normal venation of which only 30 graded 

 to sooty, and 160 defective of which only 28 graded to sooty. 

 From sixty daughters of stock 5 (oDjjSuDx) females there were 

 produced orange males, 1,926 of normal venation of which only 

 65 graded to sooty and n defective with none grading to sooty. 

 The small proportion of % males grading to sooty indicates 

 that freak 185 lacks s n . The excess of defective over normal 

 from daughters of stock 3 females, and the presence of 1 1 de- 

 fective from daughters of stock 5 females indicate that freak 185 

 transmitted d x . 



Mosaic character of eyes and mesosternum indicate that the 

 first oocyte division giving rise to this freak was equational for 

 orange and probably for sooty. Defective r 4 indicates a minor 

 factor for defect remaining in the egg. Breeding tests indicate 

 composition of testes to be oS H D x . Maturation may be repre- 

 sented as follows: 



First polar body OoS II s II D x (d x ) 



' . 



Cleavage nuclei Os n (D x ) [oS^dx 



Freak 264. The orange impaternate female, freak 257, 

 ooD n D H Ww, arose from mixed ancestry and probably carried 

 at least one minor factor for defective venation, d x . An orange 

 wrinkled son, oD n wd x , was crossed to a female of L. stock 9 



