174 REPORTS ON THE STATE OF sCIENCE.—1914. 
The data from which the above averages are calculated are as 
follows :— 
Yellow x yellow. See list. 
Yellow x other colour. See list. 
Black x black gave 7, 5, 3, 6, 7, 9, 4, 2, 8, 4, 2, 5, 4, 4, 4, 3, 2, 6, 5, 7, 7, 3, 4. 
Black x blue gave 3. 
Black x chocolate gave 2, 2, 4, 2. 
Black x silver-fawn gave 5, 6, 6, 8, 4, 6, 2, 5, 5. 
Blue x blue gave 7, 4, 4, 7, 2, 4, 3, 6, 3, 2, 3, 5, 4, 6, 5, 4, 3, 8, 2, 2, 5 
ae x chocolate gave 5, 7, 5, 2, 7, 5, 6, 5, 4, 4, 7, 8, 7, 4, 3, 5, 2, 4, 6, 7, 4, 7, 
3, 6, 
Mics x black. See black x blue. 
Phocalete sx: chocolatey; Steer Sree earthy BENE ee eee 
*Snouelsle x silver-fawn gave 5, 3, 1, 7, 4. 
Chocolate x blue. See blue x chocolate. 
Chocolate x black. See black x chocolate. 
Silver-fawn x silver-fawn gave 7, 3, 6, 6, 6. 
Silver-fawn x black. See black x silver-fawn. 
Silver-fawn x chocolate. See chocolate x silver-fawn. 
Albino x albino gave 5, 2, 4, 6, 6, 5, 6, 4, 5, 6, 5, 4, 6, 
Albino x colour other than yellow gave 4, 3) ‘4, ‘1, 7 
6, 3, 3, 2, 4, 1, 2, 2, 2, 4, 8, 4, 2, 5, 6, 3, 4, 5, 5, 6, 2 AL 
APPENDIX B. 
Albino Mice. 
I crossed many of my mice with albinos in the process of testing 
their genetic behaviour. There appears to be no need to set out the 
results in detail, but the following points may be noted :— 
The size of litter in the three types of mating—albino x albino, 
albino x yellow, and albinox colour other than yellow—is given in 
Appendix A. 
The colour composition of the litters from albino x colour con- 
formed to the rules now well established for the heredity of albinism 
in mice. 
Fourteen of the matings albino x colour yielded some albino young; 
the total young from these matings numbered 37 albino: 30 coloured, 
expectation being equality. 
APPENDIX C. 
Piebald Mice. 
_ A piebald chocolate-and-white mouse appeared in a litter born to a 
chocolate mouse bought in kindle from a dealer. I bred from it to the 
F, generation in order to assure myself that it acted as a recessive to 
self-colour. 
References. 
BATESON . 1903 . ‘Proc. Zool. Soc.,’ London. 
————— . 1909 . *Mendel’s Principles of Heredity’ (coloured illus- 
trations of mice). 
Baur . . 1907 . ‘Ber. Deutsch. Bot. Ges.,’ vol. xxv. 
