SLUGS IN GREENHOUSES IJ 



over the surface of a pot in which is growing a Dcndroljium 

 nohile, a Cattlcya, Vanda, or similar upright plant for a score 

 of times without ever attempting to ascend into the head of the 

 plant unless it is in bloom, in which case they are certain to find 

 their way straight to the flowers ; after which they will descend, 

 and return to some favourite hiding-place, often at the opposite 

 end of the house." ^ Mr. R. Warner has " actually seen many 

 little slugs suspending themselves by slime - threads from the 

 rafters and descending on the spikes of the beautiful Odonto- 

 glossum alexandrae ; and thus many spikes, thickly wadded round 

 with cotton wool (which the slugs could not travel over), and 

 growing in pots surrounded by water, had been lost." - Perhaps 

 the most singular instance of a liking for a particular food is 

 that related by Mr. E. Step.^ In a London publishing house, 

 slugs were observed, during a period of nearly twelve months, to 

 have fed almost nightly on the colouring matter in certain book- 

 covers, and though the trails were often seen over the shelves, 

 and cabbage and lettuce leaves laid down to tempt the creatures, 

 they continued their depredations with impunity for the time 

 above mentioned. 



Zimnaea peregra has been observed feeding on old fish-heads 

 thrown into a dirty stream, and a large gathering of Zimnaea 

 stagnalis has been noticed feeding upon an old newspaper in a 

 pond on Chislehurst Common, ' so that for the space of about a 

 square foot nothing else could be seen.' ^ 



Tenacity of Life. — Land Mollusca have been known to exhibit, 

 under unusual conditions, remarkable tenacity of life. Some of 

 the most noteworthy and best authenticated instances of this 

 faculty may be here mentioned. 



The well-known story of the British Museum snail is thus 

 related by Mr. Baird.^ On the 25th March 1846 two specimens 

 of Helix desertorum, collected by Charles Lamb, Esq., in Egypt 

 some time previously, were fixed upon tablets and placed in the 

 collection among the other Mollusca of the Museum. There they 

 remained fast gummed to the tablet. About the 15 th March 

 1850, having occasion to examine some shells in the same case, 



^ Garden, v. p. 201, quoted hy Kew, ut si(p. 



- Kew, lit sup. ^ Science Gossip, 1883, p. 163. 



* T. D. A. Cockerel], Science Gossip, 1885, p. 211. 



5 Ann. Marj. Nat. Hist. (2) vi. (1850) p. 68. 



