96 RAMBLES IN SEARCH OF SHELLS. 



naturally extended. Most fluids contract the slugs 

 when they are immersed in them. The slugs should 

 be killed whilst crawling, by plunging them into a 

 solution of corrosive sublimate, or into benzine. 

 Models in wax or dough are sometimes substituted 

 for the animals. A writer in the " Naturalist " * gives 

 a process for the preservation of slugs, which he 

 states to answer admirably, and to be very superior 

 to spirit, glycerine, creosote, and other solutions : 

 " Make a cold saturated solution of corrosive sub- 

 limate'; put it into a deep wide-mouthed bottle, 

 then take a slug you wish to preserve and let 

 it crawl on a long slip of card. When the tentacles 

 are fully extended, plunge it suddenly into the 

 solution ; in a few minutes it will die, with the 

 tentacles fully extended in the most lifelike 

 manner, so much so, indeed, that if taken out of 

 the fluid it would be difficult to say whether it be 

 alive or dead. The slugs thus prepared should not 

 be mounted in spirit, as it is apt to contract and 

 discolour them. A mixture of one and a half parts 

 of water and one part of glycerine has been found to 

 be the best mounting fluid ; it preserves the colour 

 * The " Naturalist," vol. i., p. 253 (1865). 



