Test for intercalary regeneration of the metameric pattern of the leafhopperEuscelis plebejus fall. (homoptera).

Immerging U-shaped germ bands of the leafhopperEuscelis plebejus were cut twice by constriction in order to combine the anterior and posterior ends of the embryo. Although these terminal parts fused in a number of cases, no intercalary regeneration was observed.In addition, the experiments revealed that constriction during anatrepsis (germ anlage extension) causes gaps of varying size in the abdominal part of the segment pattern.The data suggest that "differential adhesion" between yolk cells and the surface of the germ anlage might play a part in the immersion of the germ anlage into the yolk.