316 



INHERITED LINKAGE VARIATIONS 



LEFT-HAND END OF NOVA SCOTIA CHROMOSOME (Cm). 



Culture 678 was derived from a female with an original Nova Scotia 

 chromosome and with black, purple, curved, and morula in its mate, 

 mated to four black purple curved males. The culture is included 

 in the totals given in table 1. It produced three curved flies by cross- 

 ing-over. These flies must have had the left-hand end of the Nova 

 Scotia chromosome, up to a point between purple and curved; but 

 the right-hand end of the Nova Scotia chromosome had been lost. 

 One of them, a male, was mated to a black purple female that had 

 the right-hand end of the Nova Scotia chromosome (C// r ). A wild- 

 type daughter was mated to black purple curved morula, and gave 

 results that will be discussed below (see table 16). A curved-morula 

 son, that must again have had the left-hand end of the Nova Scotia 

 chromosome, was mated to a similar black purple female; and a wild- 

 type daughter was once more back-crossed to black purple curved 

 morula in culture 752. This time, however, it was decided to get the 

 influence of the left-hand piece of the Nova Scotia chromosome with- 

 out the presence of the right-hand end. A curved morula male from 

 752 was accordingly mated to a star black female of an unrelated 



8' b 



stock. A daughter, of the constitution 



with the end of 



c m r ' 



the Nova Scotia chromosome opposite star and black, was mated to 

 black purple curved speck males, in culture 776. The result was 106 

 non-cross-overs, cross-overs between star and black, and 38 cross-overs 

 between black and curved. Further tests with descendants of 776, in 

 which the same piece of the Nova Scotia chromosome was present, gave 

 the results shown in table 12 (culture 776 itself is included). 



TABLE 12. C ne . 



* Done with H. H. Plough, and already reported by him (Plough, 1917). 



Clearly we have here the same results for star purple as in the case 

 of the original Nova Scotia chromosome; but for purple speck we have 

 nearly the usual result. Q Q 



Culture 259 contained a female of the constitution r 



b p r v g a r s p 



(original Nova Scotia chromosome), and two stock 6 p r v g a r s p males. 



