Abstract
The dorsal bodies (DB) have been investigated in mature Helix aspersa in different physiological states and in adult animals maintained under short- or long-day light cycles. Morphological criteria as well as a quantitative electron microscopical study do not indicate striking differences in DB cells of snails reared at different photoperiods. Compared with control animals, hibernation causes a reduced activity of the DB, whereas in egg-laying snails, the increase in DB cell size and protein synthesis, the large decrease in the amount of lipids and the mitochondrial changes suggest an activation of DB hormone synthesis.