Embryonic development in two species of Chesias (Lepidoptera: Geometridae)


  • *Department of Zoology, The University, Reading, Berkshire.


The embryonic development of Chesias legatella Schiffermiiller and C. rufata Fabricius is described and compared. Eggs of C. rufata develop in approximately nine days at 20°C; those of C. legatella overwinter and hatch after five or six months. The morphology of the developing embryo is described in detail and is essentially similar in both species except during the formation and early development of the germ band. Morphogenesis is divided into a number of arbitrary stages and the relative duration of the different stages is compared in these and other species.