in Mendelian Ratios. 427 
few litters of each individual size, but a fair comparison results 
when the figures for litters of all sizes are totalled together. 
Table A shews what is meant. The figures in ordinary type give 
Taste A. Hybrids of Japanese waltzing mice x albinos paired 
together : expectation of albino 25°/,. Observed (roman) and 
calculated (italic) numbers of litters of each size with 0, 1, 2,... 
etc. albinos. Data from Darbishire, Biometrika, Ut. 
Number of albinos in the litter 
Size of | Total 
litter | | 6 litters 
‘ b | or || 
| 0 1 2 3 4 ) more || 
— ra) 
1 7 = | 7 
DES | Ts | | 
2 3 7 i | 11 
619 | 412 | 0-69 
3 Pemok ns 4 til 16 
6:75 | 6:75 | 2:25 | 0:25 | 
4 5 9 3 a Ae | 17 
Eso 718s | F259 O80) lpn 0-04 
5 9 9 3 3 1 1 26 
Gly | 1028 | 6-86 | *228 | 0-88. |) 0-03 
6 8 9 8 6 = = _ 31 
Geel OF 9-200 4-09) 1-02) | Ot | 0:01 -|| 
7 Tees. 4 3 2 1 =f i aa | 
147 | 343 | 343 | 1:90 | 063 | 0-13 | 0-01 || 
8 = ~ ie |e = — — 1 
HO1O 0:27) 0-31 | 0-21 | 0:09 \ 0-02) | — 
9 ress a 1 te =a ee ee 1 
| 008° | 0:23 | 0:30 | 0:23 | 0:12 | 0-04 | 0-01 | 
| | | 
| 
Total obs. : 40 43 24 11 2 1 | = ji 1a 
eale.: || 86:92 | 45:04 | 26°63 | 9:76 | 2:28 | 0°86 | ‘03 \| 121-02 
the observed numbers of litters of each size with a specified 
number of albinos; the italic figures are those calculated from 
the respective binomial series. The expectations being 3/4 and 
1/4, the expected proportions of litters of 1 with no albinos and 
1 albino are 3/4 and 1/4: the expected proportions of litters of 2 
with 0, 1, and 2 albinos 9/16, 6/16 and 1/16—and so on. The 
