photoperiod is the main cue that triggers supercooling ability in the land snail, helix aspersa (gastropoda: helicidae). | helix aspersa hibernates in brittany (western france), where it may experience subzero temperatures. studies on cold hardiness, although scarce in land snails, have shown a seasonal variation in supercooling ability, associated with high temperatures of crystallization (tc). in the present work, two key environmental factors, temperature and photoperiod, were studied to elucidate, how they may affect the enhancement of supercooling ability in the snails from the end of summer to winter. nine gro ... | 2001 | 11748935 |