A Sport of the Silk-Worm, Bombyx Mori L., and its Hereditary Behavior. 185 
Table 7. 
Worms from egg-batch No. 2 of parentage No. 26, which produced red and black 
worm in the proportion 1R:1B 
A. Mating between red worms. 
Date of Number of ‘ 3 
ee E Date of hatching | Kind of worms hatched 
oviposition egg-batches — 
18—1 3/9/06 16 7/10/06 All red worms 
et 
17/4/07 
They also remained true to the parents. 
B. Mating between black worms. 
Kind of worms 
No. of Date of Date of hatched Total 
egg-batches | oviposition | hatching }———— 
red ad [Doe | er 
I 18—23/9/06 |7/10/06 et] 134 (28.68 Te Ee en ee 334 468 
ae 
Ze 33 128 161 the rest eggs died 
ie 64 (29.35 %) 154 | 218 
4*) II 40 51 the rest died 
5 84 (27.27 %) 226 Bir 
6 70 (28 %) 180 | 250 
7 81 (25.87%) 232 | 313 
*| 
| 208 (25.08%) 622 830 
ee) 
£1*) 36 125 161 the rest died 
12 5 (13 88%) 31 36 this is the total 
13 63 22.5 %) 217 280 
14 102 (26.7 %) 280 382 
15*) 39 41 80 the rest died 
16 27 (23.47%) 88 IIs 
Total!) 839 2,364 | 3,203 
Mendelian 800 2,402 
expectation 
Deviation 38 
Now we see that every mating produced red and black worms 
nearly in the proportion of one red to three blacks and thus the 
supposition in the previous generation was proved to be true. 
Back-Crossing. 
I. Hybrid black >< red, or DR=R. 
Q Dark worms from No. 3 of the fourth generation. 
13 Red worms from No. ı of the fourth generation. 
1) Excluding those marked with an asterisk. 
