5370 Mollusks. 



these had been in full play, when the animal required considerable 

 nourishment to supply the rapid absorption consequent upon growth 

 of body and the secretion of the shell, the supply of nutriment must 

 utterly have failed to meet the demand, and the mollusks must have 

 perished. In the month of October, however, Mollusca, for the most 

 part, ha\e completed their growth for the year. The functions and 

 secretory powers having been heavily taxed, as Mr. Lowe has recently 

 shown, during a short period are comparatively dormant, and all the 

 vital functions are gradually entering upon that sluggish and semi- 

 torpid state in which the winter is passed. I am of opinion, therefore, 

 that the vital powers of the Mollusca being in a state of comparative 

 inactivity at the time they were inclosed, rendered them able to bear 

 up against the severe trials to which they were subjected ; that these 

 circumstances being unaltered as the seasons came round, the animals 

 remained in their comparative torpor, since the functions were not 

 called into activity by any sensible rise in the temperature, or by the 

 stimulating influence of the sunlight. The facts that none of the 

 Mollusca increased in size during their incarceration, and that they 

 always appeared to be in a very lethargic state, seem to add weight to 

 this supposition. 



There remain a few observations to be made upon the results. 



The first point that may strike the reader is that the Mollusca lived 

 during such a lengthened period without food. They had not much, 

 certainly, to be divided among forty mouths, which remained to be 

 filled after the death of the eighteen Limnei ; still they had some — 

 the two little scraps of leaf and the two cotyledons. I think it, more- 

 over, highly probable that they fed upon the bodies of their 

 deceased friends, for, although naturally vegetable feeders, many inland 

 Mollusca have been known to become animal feeders : I have myself 

 seen Arion empiricorum, Limax maximus and agrestis, and Helix 

 aspersa devour decomposed animal matter. Granted, however, that 

 they ate everything that was in the bottle, animal as well as vegetable, 

 they must have been even then on extremely " short commons." The 

 fact, however, that inland Mollusca can live for very lengthened 

 periods of time without food is already known. Mr. Woodward, in his 

 excellent i Manual of Mollusca' (published as one of Weale T s Rudi- 

 mentary Treatises), at pp. 18, 19 gives many instances; I will extract 

 the last: — " The most interesting example of resuscitation occurred 

 to a specimen of the desert snail [Helix desertorum) from Egypt, 

 chronicled by Dr. Baird (Ann. Nat. Hist. 1850). This individual was 

 fixed to a tablet in the British Museum, on the 25th of March, 1846 ; 



