Hexaptera, a Homoeotic Mutant in Drosophila Melanogaster

CCORDING to BATESON the term "homoeosis" refers to alterations of A an organ of a segmental series from its own characteristic form to that of some homologous organ of the series. Several homoeotic mutants have been discovered in Drosophilia melanogasfer, which result in replacement of certain organs of the normal fly by parts resembling other organs. Thus, arista is changed into a leg in aristapedia (BALJCASHINA 1929), and into wing-like structures in a mutant mentioned by GOLDSCHMIDT (1945). Compound eyes bear palp-like structures in ophthalmopedia Mouth parts are changed into leg-like organs or into aristae by proboscipedia Halteres are changed into wings in bithorax Wings are changed to halteres, "palps", and legs by tetraltera