i8 
Scientific Proceedings (40). 
Another mutant that shows itself to be sex limited in inheritance 
has appeared in these same cultures. A few males appeared with 
wings half the normal length. 
One of these short-winged males bred to a normal female of 
another stock produced long- winged males and females. These 
inbred have produced 5,856 long- winged males and females, and 
85 short- winged males (no short-winged females). Here again 
the character is transmitted from the grandfather to some of his 
grandsons but to none of his 3,000 granddaughters. 
The next question to determine is the relation in inheritance 
of these two characters, both sex limited. At present I can give 
only a provisional statement, since the experiment is still in 
progress. 
In the experiment last described the short- winged male had 
red eyes. He was paired to a long- winged white-eyed female. 
The offspring consisted of red-eyed females and white-eyed males 
(the normal result for this combination). All had long wings. 
These were inbred and produced in the second generation red- 
eyed, long-winged males and females, white-eyed long-winged 
males and females, white-eyed short-winged males and red-eyed 
short- winged males. 
In other words, neither white eyes nor red eyes were limited to 
the short- winged males. 
The results are difficult to explain fully owing to the great 
deficiency of the short-winged forms, due possibly to incompati- 
bility. Let R = red eyes; W = white eyes; L = long wing; 
S = short wing; X = the sex factor; then: RXSWS = the red- 
eyed short-winged male, and WXLWXL = the long- winged white 
female. Their germ cells will be 
WXL-WXL 
RXS - WS 
WXLRSX - WXLWS 
red $ long white long 
The germ cells of these individuals, and the results of their 
combination should be: 
WXL-WXS-RXL-RXS, red $ 
WXL-WS white cf 
WXLWXL = white 9 long wings 
WXLWXS = " " 44 
WXLRXL=red " " 
