STRAIN AND INDIVIDUAL IDIOSYNCRASIES 3I 



Fg Hyb. white larva, salmon cocoon X hyb. white larva, salmon 



cocoon; produced all white larvae and 10 white and 22 



salmon to golden-yellow cocoons. 

 Fi ^ Bagdad X $ Ital. Sal,; produced all zebra larvae and 19 

 white and 35 salmon to yellow cocoons. 



Fj Hyb. zebra larva, salmon cocoon X hyb. zebra larva, salmon 



cocoon ; produced y^ zebra and 28 white larvae and 47 white 



and 38 salmon to golden-yellow cocoons. 

 F2 J* Hyb. zebra larva, salmon cocoon X $ hyb. zebra larva, 



white cocoon; produced 156 zebra and 39 white larvae and 



59 white and 61 salmon to yellow cocoons. 

 F2 Hyb. zebra larva, salmon cocoon X hyb. zebra larva, salmon 



cocoon; produced 123 zebra and 55 white larvae and 17 



white and 99 salmon to golden cocoons. 

 Fg Hyb. zebra larva, salmon cocoon X hyb. zebra larva, salmon 



cocoon; produced 50 zebra and 15 white larvae and 17 white 



and 44 salmon to golden cocoons. 

 F2 Hyb. zebra larva, salmon cocoon X hyb. zebra larva, salmon 



cocoon; produced 60 zebra and 19 white larvae and 15 white 



and 45 salmon to golden cocoons. 

 Fg Hyb. zebra larva, salmon cocoon X hyb. zebra larva, salmon 



cocoon; produced 34 zebra and 17 white larvae and 19 white 



and 26 salmon to golden cocoons. 



In these series are to be noted the regularly Mendelian behavior of 

 the larval patterns (in many of the lots the numbers were either so 

 reduced by disease or by the necessities of space, food and time of 

 care-takers as to obscure the Alendelian proportions), the marked in- 

 dividual idiosyncrasies (reversal of dominance, splitting of colors 

 equally in first crosses, impure recessive behavior in second (hybrid) 

 generations, etc., etc.) in the cocoon color inheritance, the constant 

 tendency for the salmon color to break into a series of graduating 

 colors ranging from the very pale salmon through to strong (golden) 

 yellow, and the influence of white toward making the salmon ex- 

 tremely pale, i. e., to produce a blending in inheritance rather than a 

 sharp segregation. But the cocoon color does not always behave 

 irregularly. In many cases it behaves in almost exact IMendelian 

 manner, and this is true whether in F^ the dominant color is salmon 

 yellow or is white. In Fo lots the splitting will then be respectively 

 3 salmon-yellow to i white or 3 white to i salmon-yellow, which 



