142 Experimental Zovblogy 
ably have been thus considered. On the other hand, there are 
also numerous instances where it seems probable that the inheri- 
tance is of a different kind. To what the results are due is not 
clear in all cases, but it seems not improbable that some of the 
domesticated races of silkworms have originated from different 
wild species, or even genera; while others have arisen under 
domestication as sudden variations. Several instances of this 
sort are given and invite special attention. Some of the races 
may be crosses, i.e. hybrids, and even although breeding true 
inter se the individuals may carry in a latent state the qualities 
of other strains. In the light of these possible complications 
we can do little more than examine Coutagne’s results as they 
stand. It is to be hoped that this most promising field of inquiry 
may be further investigated. 
Coutagne distinguishes between (1) an “alliage homogéne,” 
or fusion, in which the hybrid character is something new and 
intermediate between the parental characters (which are united 
or fused ‘“‘fondus’’); (2) a ‘‘mélange hétérogéne,” or mixture, 
in which some of the hybrids are like one parent and some like 
the other in respect to a particular character, and still others inter- 
mediate; (3) a “‘liquation” or separation in which there is no 
fusion of characters in any of the individuals, but they are strictly 
like one or the other parent type. 
The inheritance of the following characters was examined by 
Coutagne : — 
1° The caterpillars (“ worms”) : 
White (with or without a masque) a, 1 mode albus 
Black a2 “ niger 
Zebra a,3 “ virgatus 
2° The cocoons: 
Yellow b,r “ flavus 
White b,2 “ niveus 
3° The moths: 
White, with or without “cendre” markings c,r “ canus 
Black c,2 “ casteneus 
