164 Oft the Preservation of Animals in Fluids. 



lias in this manner been deposited, it is covered by a layer of 

 cotton or tow, to prevent the fishes from being damaged by the 

 rolling of the vessel. In general, the cask should only contain 

 two-thirds of fishes, the rest of the space being occupied by cot- 

 ton or flax. 



The principal objections to this method is, that it does not 

 completely guard against the putrefaction of the fishes, especially 

 in warm climates. Peron proposed another method, which he 

 found perfectly efficacious, and which is as follows : The animal is 

 to be washetl before emersion in spirit, in sea water, vinegar, 

 rum, tafia, or camphorated spirits, according as these substances 

 may be most easily procured. The mucosities are to be removed 

 by a hair brush. The animals are then suspended in the fluid, 

 but they are so suspended that they can float at the surface, which 

 is managed by attaching pieces of cork to them. In some cases, 

 round plates of cork are taken, and the animal fastened round 

 its edge, by means of brass wire or pins. Reptiles require an 

 additional means, which consists in forming cork spirals, into 

 which the bodies of serpents are made to pass. Inclosed in 

 this manner, and bathed on all sides by the alcohol, these ani- 

 mals are perfectly preserved. Incisions are to be made in the 

 belly of large animals, in order to admit the alcohol to the vis- 

 cera, but the latter ought not to be removed, or if this is ne- 

 cessary, they must be separately preserved, as they are of the 

 greatest importance for the study of the organization. The in- 

 dividuals are all numbered, and a corresponding mark attached 

 to their descriptions. 



A little practice will soon enable any one to manage these de- 

 tails with facility, and although they may be at first somewhat 

 troublesome, the labour is amply compensated by the advantages 

 gained. Animals thus put up, can experience no damage from 

 the rolling of the vessel, or from the excessive heat of the Torrid 

 Zone. 



Various means for closing the vessels have long been used, 

 which vve shall now point out. Peron finding many of them in- 

 sufficient, substituted others which he found to answer his 

 wishes. Parchment, covered with a solution of sealing wax 

 in pure alcohol, has long been used ; but parchment is readily 

 reduced to a putrid state by humidity and heat, and wax is 



