IN THE SECOND CHROMOSOME. 



311 



Table 6 shows the results obtained from second broods, 1 produced 

 by females containing a Nova Scotia chromosome. These data were 



TABLE 5. Tests of all females bearing one Nova Scotia chromosome 

 (region from star almost to speck) . 



collected in order to find out if there is a change in the linkage value 

 as a female grows older. The percentages are so small, however, that 

 a comparison with first broods can give no significant result. The 

 small percentages also make impossible a satisfactory study of 

 coincidence in tables 1, 3, and 4. 



TABLE 6. One original Nova Scotia chromosome, second broods. 



Culture 69, referred to above (p. 307), contained a female of the 



... ,. Nova Scotia ~ , . . . 



constitution , mated to a v g s p male. One vestigial male, 



v, s p 



produced by crossing-over and possessing, presumably, only the ex- 



111 First brood" and "second brood" are terms applied to the offspring produced when a 

 female is kept in one bottle for 9 or 10 days (first brood) , and then transferred to another bottle 

 for a second period of 9 or 10 days (second brood). The division is an arbitrary one, and doea 

 not correspond to any "rhythm" in the production of eggs. 



