OH the Chitonidce. 33 



top, is to be filled with fresh water to overflowing, and the animals 

 thrown into it : they are to be covered over with flat even glass, and in 

 this prison-house they are suffocated and destroyed, the organs remaining 

 extended in their natural attitudes. It is better to use separate glasses, 

 as the animals,* il' placed together, by crawling over each other, often 

 in fright retract their organs ; and they are to be kept as still as possible. 

 When quite dead, they are to be thrown, without loss of time, into 

 weak, and afterwards stronger spirit : some are to be preserved naked, 

 while the shells of others may be retained, the spire being perforated or 

 cracked, for the admission of the antiseptic fluid to the spiral turns of the 

 abdomen. It does not, however, so well answer for the Ampnllariadcn, 

 and those genera which possess branchiae as well as a respiratory cavity 

 (Respiratorium.) On these it would be advisable to try the shock of an 

 electric battery. Xeritince are destroyed with great difficulty: some 

 which were even kept close in salt water seemed to have the power of 

 purifying it, and rendering it fit for respiration, while many large air- 

 bubbles were generated in the glass. Some power of this kind would 

 be very valuable to those species which inhabit maritime ponds, the wa- 

 ters of which, nearly dried up at certain seasons, must be stagnant and 

 unwholesome. 



The marine univalves, if kept still in separate vessels thus covered, 

 will die in their natural attitudes, though not without some exceptions, 

 which the zoologist will be taught by experience. All, however, are 

 liable to deceive the operator. Although lying reversed, and apparently 

 lifeless, many, when thrown into spirit, will possess sufficient muscular 

 power to withdraw within the shell, when suddenly stimulated by the 

 ardent spirit. It would be safer to pour oflF gently the stale sea-water, 

 and to have boiling water dashed on them, to secure the success of the 

 operation. 



Many of the minuter shells, as soon as the animal has been described, 

 are to be thrown into spirit, and the operculum in situ may be observed 



• In warm countries, if the smaller Land Mnllu.tca are captured at a distance 

 from home, they should be placed in tin boxes, with only damp leaves, and 

 ail water carefully poured out: without this precaution, the steam generated 

 during the night will be fatal to the captives. 



Vol. V. c 



