Experimejits with Snails, Moths, and Beetles 145 



having white worms, yellow cocoons, and white moths. All of 

 the worms were black, half of the cocoons were yellow, and half 

 were white (180 and 188), without any intermediate ones. 



In a fourth case an individual (female) w^ith w^hite worms, 

 cocoons, and moths was crossed with another (male) having 

 black worms and moths, but yellow cocoons. All the cocoons 

 were white. The worms were 265 black like the father and 

 253 white hke the mother; some of the moths were white, others 

 black, others intermediate. In the group of 265 black worms 

 there were no more black moths than in the group of 253 white 

 worms. Thus the characters black or white worms and the 

 characters black or white moths have no mutual relation. 



In a fifth case, the female of a variety " Jaune Var" was used 

 that has the black character of the worm and of the moth almost 

 completely "fixed," but fixed only recently, while the yellow of 

 the cocoon had been fixed for a long succession of generations. 

 The male w^as of the race "Blanc des Alpes" and had white 

 characters throughout. The result of the cross gave white co- 

 coons, the paternal type — the reverse of what occurred in other 

 cases where the white was maternal. The worms were 258 

 white like the father and 182 striped hke the mother (3 to i). 

 This predominance Coutagne attributes "to the ancestors of 

 the white worms of the mother; possibly if the striped char- 

 acter had been fixed for a greater number of generations there 

 would have been an equality between the white and striped 

 worms." The questionable character of this explanation is at 

 once apparent in the next experiment that Coutange gives, in 

 which the same types were crossed as before and all the worms 

 were striped. 



(6) It has been found that white cocoons dominate over yellow, 

 but in another combination the reverse was found to be the case, 

 showing that there is no absolute rule for all races in regard to 

 the inheritance of white versus yellow. 



(7) After crossing individuals of two races which give offspring 

 showing the character of one parent, it often happens that the 

 concealed character reappears in the following generations. 



