Neuroendocrine organs of the lemon butterfly, Papilio demoleus L. II. The corpora cardiaca allata complex of the adult

Abstract

The retrocerebral endocrine organs of the adult lemon-butterfly, Papilio demoleus, have been described. The organs are subaortic lying closely behind the brain. While the nervi corporis cardiaci I (NCCI) originate from the protocerebrum of the brain, the NCCII seem to take their origin in the tritocerebrum in common with another nerve named earlier as the tegumentary nerve. The corpora cardiaca (CC) and corpora allata (CA) are closely approximated to each other obliterating the nervi corporis allati (NCA) which are conspicuous in the larva of the same species. An intercardiacal bridge (ICB) connects the CC of the two sides and acts as a possible centre of distribution for the neurosecretory material (NSM) to the gut. Histological evidence suggests that the NSM inside the CC remains intraaxonal without being primarily unloaded in the organs for storage. The intrinsic secretory cells of the CC are intimately associated with the neurosecretory fibres from the brain and bear fairly thick axons. No NSM could be detected in the CA of this insect.