146 Experimental Zoology 
When Blanc des Alpes are crossed with Jaune Var, all the off- 
spring have yellow cocoons. The next generation gave yellow 
and white cocoons with none intermediate; the proportion of 
yellow averaged in fifteen lots 75.2. Here there seems to be 
an approach to one fourth that strongly suggests the Mendelian 
ratio. In other cases, however, an average of 49.3 per cent was 
obtained. The evidence here is opposed to this interpretation, 
unless one of the races itself had a latent character that did not 
appear until the second generation. 
(8) When two crossed races give a separation in equal parts 
of the two characters, the following generations give equally 
again the separation of the two characters without its being pos- 
sible to realize their fusion in a single individual. 
For example, two types were crossed, each having striped 
worms and yellow cocoons. 
The offspring gave four classes : — 
Worms Cocoons 
I 236 striped yellow 
2 80 striped white 
3 89 white yellow 
4 34 white white 
In another case the female belonged to a race with white worms 
and cocoons, the male striped and yellow cocoons. 
The crosses 
were : — 
Worms Cocoons 
I 95 striped yellow 
2 84 striped white 
3 103 white yellow 
4 109 white white 
Seven other combinations are given, but until some principle 
running through these cases can be formulated it is needless to 
recount all the results here. It is true that Coutagne attempts 
to show that the rule in subsequent generations is such that the 
inheritance of the contrasting characters follow the sequence of 
