FOOD, HABITS, ETC. 75 



Common Garden Snail {Helix aspersa) has been 

 known to survive in captivity for nine years. 



Less is known about the duration of life among 

 the Cephalopoda, but it is said that Rossia does not 

 live for more than a year, and the Octopus not more 

 than four years. 



As regards tenacity of life, many instances are on 

 record of Mollusca surviving under very adverse con- 

 ditions (see also ante, pp. 52, 53 and 71). Among the 

 more remarkable the following may be cited : Speci- 

 mens of Littorina muricata were kept out of water for 

 a whole year and then found to be alive. A Pond 

 Mussel was sent to Dr. Gray from Australia that 

 lived 498 days after it was taken from the pond, 

 having in the interim been only twice in water to see 

 if it were alive. Some specimens of Ampullaria 

 purposely placed in a drawer in Calcutta were found 

 alive after five years, despite the warm climate. 



Those molluscs, however, which are most accus- 

 tomed to " summer sleep " seem to come off best, 

 and Land Snails will stand months and years of 

 close confinement without food. 



A specimen of Helix Veatchii, from Cerros Island, is 

 said to have existed without food for six years. The 

 most striking instance, perhaps, is the well-known 

 one of the specimen of Helix desertorum from Egypt, 

 that was stuck down on a tablet in the British 

 Museum on March 25, 1846, and found on March 7, 

 1850, to be alive : released and revived, it lived in 



