A cinematographic study of the embryology ofDrosophila melanogaster.

In connection with studies on the effect of genetic abnormalities on development, a film was made of the normal development of theDrosophila embryo. Time-lapse motion technique was used, and this made it possible to make new observations on those phases of the development which involve large re-arrangements of the embryonic material, in particular on blastoderm formation, gastrulation and involution of the head. These new observations have been incorporated in an account of the complete development of the embryo up to the time of hatching.