Figure 8.

 Wild-type imaginal discs double-labeled for ss transcript (blue) and Dll protein (brown). Small arrowheads indicate the proximal extent of ss expression; large arrowheads indicate the proximal extent of Dll expression. In early third instar leg discs (A), the proximal extents of ss and Dll expression coincide; later discs show Dll expression more proximal than ss (B). In antennal discs, Dll expression is always more proximal than ss (C). Scale bar, 50 μm.