I was looking at Ralph Davis's website and I noticed that there are different axanthic lines.....the Axanthic_VPI and Axanthic_Jolliff are two.

The notes on his site tell us that these two lines are incompatible. What does this mean exactly? Does this mean that the two recessive phenotypes when crossed produced F1 offspring that were all normal?

Has anyone tired matting two of the F1 offspring together to see what happens in the F2 generation?