Histological studies on the neuroendocrine organs and retrocerebal complex of Crynodes peregrinus Fuessly (Chrysomelidae-Coleopt.).

The neuroendocrine system of Crynodes peregrinus has been described by using Alkehyde-Fuchsin technique (AF) on whole amounts and sections. Four groups of neurosecretory cells are present in the brain--including the two median groups with 18-20 cells each and two lateral groups with four cells each. The neurosecretory material (NSM) reaches the corpora cardiaca (CC) by nervi corporis cardiaci I. The CC is divisible into two distinct parts--central nervous part surrounded by the cellular cortical zone. The NSM of cerebral origin is stored and released from the CC. Intrinsic cells are found to be absent in the CC. AF positive material is found also in the corpora allata.