CROSSINGOVER IN DROSOPHILA 



173 



from one tube to another at exactly two day intervals in all cases. 

 This introduced a slight element of uncertainty which was cor- 

 rected in table 14. In this latter table a cold test was also run 

 in order to give added confirmation to the results already re- 

 ported. The two groups of data are as follows: 



TABLE 13 

 b pr c 



Control Nos. 409-415. Hatched and mated at 22°C. 



November 8. 

 November 10. 

 November 13. 

 November 15. 

 November 17. 

 November 21 . 

 November 23. 

 November 25. 

 November 28. 

 November 30. 

 December 2. 

 December 5. 

 December 8. 



69 

 50 

 55 

 93 

 98 

 72 

 51 

 95 

 77 

 40 

 55 

 53 

 43 



Nos. 402-407. Hatched at 22°C. Incubator at 31° from first to seventh day 



November 6. 

 November 13. 

 November 15. 

 November 17. 

 November 21. 

 November 23. 

 November 25. 

 November 28. 

 November 30. 

 December 2. 

 December 5. 

 December 8. 



284 

 52 

 69 



87 

 74 

 82 

 71 

 56 

 73 

 65 

 33 



121 



