Figure 5
From: Spalt expression and the development of melanic color patterns in pierid butterflies
Cells of the future M3 black spots contain a factor that differentiates black scales. A) Operated P. rapae pupae where small rectangular pieces of cuticle attached to dorsal epidermis are exchanged from the area where the anterior spot develops into a more distal location on the wing (marked with *) at 2.5 h post-pupation. B) The adult wing pattern at the distal grafted site displays black scales with abnormal polarity resulting from the rotated graft.