Inheritance of the Elytral Color Patterns of the Lady-Bird Beetle, Harmonia axyridis Pallas

The inheritance of elytral patterns of the lady-bird beetle, Harmonia axyridis Pall, was analyzed genetically. 2. The results tend to show that the plain yellow elytron succinea is a simple recessive to any form with black-margined patterns. 3. Among the black-margined beetles, there were three types of patterns analyzed, viz., conspicua, spectabilis and aulica. The genetic results indicate that these characters are each due to an independent Mendelian factor with conspicua epistatic over spectabilis and the spectabilis over aulica in a series. 4. In adapting the symbol A for aulica, S for spectabilis and C for conspicua, the genetic formula for succinea (also for frigida and 19-signata) is therefore aa bb cc; for aulica, AA ss cc; for spectabilis, aa SS cc. (or AA SS cc); and for conspicua, aa ss CC (or AA ss CC or aa SS CC or AA SS CC). The authors wish to express indebtedness to Dr. C. B. Bridges and to Professor Th. Dobzhansky, of the California Institute of Technology, for their suggestions of the nomenclature used in describing the different variations and for their many other constructive criticisms of this paper.