498 University of California Pnhlications in Zoology ["Vol. 13 



In the F2 generation of X two extras were bred together. Subsequent 

 generations from this cross were called X-. The same thing is true 

 in the A family in the Fj generation, and subsequent generations are 

 called A-. 



Tables III, IV, V, and VI show the results of crossing normals 

 with extras in successive generations. Table VII shows the crosses 

 between extra and extra. 



The extras used for breeding in the tables below appeared in the 

 crosses of normal with extra in Table I. 



TABLE III 



Fo Results of Matings Between Normal axd Extra Fi Sibs 



Per 

 Family — Bottle letter N. ex. N. ex. cent 



Y d ? c^ 73 7 6.25 



i c{ 5 48 9 1.5. 



j 5 J' 102 2 1.96 



e J' 2 48 9 15.79 



A5 a ? d" 38 , 5 13.15 



TABLE IV 

 F3 Results op Matings Between Normal and Extra F„ Sibs 



Per 

 Family — Bottle letter N. ex. N. ex. cent 



Y A c^ $ 7 00 ' 



B c? ? 29 2 3.22 



C ? J' 9 00 



i ? c? 100 5 5.66 



e J' 5 100 3 33.3 



TABLE V 

 F4 Results of Matings Between Normal and Extra F3 Sibs 



Per 

 Family — Bottle letter N. ex. N. ex. cent 



X5 e c^ 5 90 1 1.11 



d c? ? 100 6 5.66 



a c? $ 23 3 12.3 



Y E= c? 2 100 3 33.3 



g^ S ^ 95 1 1.68 



A5 c^ J' 2 60 4 6.2 



TABLE VI 



F5 Results of Matings Between Normal and Extra F^ Sibs 



Per 

 Family — Bottle letter N. ex. N. ex. cent 



X A3 c? $ 60 3 4.7 



A, S 9- 50 1 1.9 



A5 ab c^ $ 80 2 2.4 



C'b (^ 2 70 3 4.1 



X5 d3 $ c^ 42 1 2.3 



