Copulation in the hermaphroditic snailLymnaea stagnalis:a review

Abstract
Male copulatory behavior of the hermaphroditic snail Lymnaea stagnalis is a complex one: the appetitive behavior consists of a number of elements which do not always appear in the same sequence and have variable durations. Backfills of the penis nerve revealed the neurons that send projections to the male copulatory apparatus. Immunocytochemical experiments have demonstrated that these neurons contain at least ten different messenger molecules. Based on in situ hybridization and chemical purification data, it is suspected that this number will probably be doubled. How the different neurons and the molecules they contain might be involved in generation of the different elements of male copulatory behavior is discussed.