Transplantation in relation to pigment formation of the integument in the larvae of the swallowtail, Papilio xuthus L

In the swallowtail, Papilio xuthus L., a switchover in the pigmentary system of epidermis occurs at the last larval molt: viz., from reddish brown xanthommatin to bluish green bile pigment. By transplantation of integument between the larvae of different developmental stages, a control by some humoral factor of the pigmentary system was revealed. But the transplantation of brain or of several combinations of known endocrine systems failed to affect the switchover of the pigmentary system at the last larval molt.