Photoperiod-dependent neural control of the activity of the neurosecretory canopy cell in the lateral lobes of the cerebral ganglia of the freshwater pulmonate Lymnaea stagnalis (L.)
(1) Biological Laboratory, Vrije Universiteit, Amsterdam, The Netherlands;(2) Present address: Department of Biological Sciences, University of Maryland Baltimore County, 21228 Catonsville, Maryland, USA