The exception proves the rule--findings of a histological study of neuroendocrine centres of anomalous first instar nymphs of cockroach Periplaneta americana (L.)
Khan, T.R.
Folia Morphologica 31(3): 263-265
1983
ISSN/ISBN: 0015-5640 PMID: 6629220 Document Number: 204584
In anomalous 1st-instar nymphs of Periplaneta americana (L.) that did not moult until a month after hatching, no neurosecretory cells could be found in the brain. Mitotic activity in the brain was very low, and the corpora cardiaca and corpora allata showed cytological signs of inactivity. These observations are presented as evidence supporting accepted theories on the neuroendocrine control of moulting.