and Freserviny Animals. 287 



served in the solution No. II. In all cases it is desirable that the 

 specimens should be allowed to die gradually in the water they in- 

 habit, when they commonly display their natural external form and 

 appendages in a relaxed state ; they should then be immediately put 

 into the solution or spirit, to prevent putrefaction, which otherwise 

 takes place rapidly. 



Cirripedia (Barnacles and Acorn-shells, or Crown-shells). 



The barnacles, or pedunculated Cirripedes, with soft stalks, should 

 be preserved in the solution No. II., or in spirits; they are com- 

 monly attached to floating timber, and the smaller species to sea- 

 weed, shells, &c. The sessile kinds (acorn-shells, &c.), which en- 

 crust the coast rocks all over the world, and are found parasitic on 

 turtles, whales, &c., should likewise be preserved in spirit, or solu- 

 tion No. II., as the included animal is necessary in some genera 

 for the recognition of the species. The colours of the pedunculated 

 should be noted whilst fresh. If the sessile kinds are preserved dry, 

 the included animal ought never to be taken out. In removing all the 

 kinds from their points of attachment care must be taken that in 

 some specimens, at least, the base, which is either membranous or 

 calcareous, be preserved. It is particularly desirable that some 

 young, as well as large specimens, should be collected. In the tro- 

 pical seas certain corals and shells contain embedded in them singu- 

 lar forms of cirripedes, which, presenting externally little more than 

 a single aperture, are easily overlooked ; such kinds had better be 

 preserved in the coi'al. Others live embedded in sponges ; two 

 genera live on whale's skin {Coronula and lubicinellci), the develop- 

 ment of which needs to be studied by specimens of the ova and 

 young ; another less-known genus (ChelonobicC) lives partly em- 

 bedded in the skin of turtles ; a third attaches itself to the manatee 

 or sea-cow ; and some small and interesting species of barnacle are 

 parasitic on sea-snakes. Lobsters, craljs, bivalve and other shells, 

 as well as floating pieces of wood, or even net corks, become the 

 habitat of animals of the class Cirripedia. It should always be 

 noted to what animals these parasitic Cirripedes are attached, as well 

 as any circumstances that may determine the period during which 

 they have remained attached. 



Crustacea {Shrimps, Sea-mantises, Cray-fish, Lobsters, Crabs, 

 and King-crabs). 



All the animals of this class are most profitably preserved in spirit 

 or solution. If they be defended by a soft, flexible, or horny cover- 

 ing, the solution No. I. answers well ; if by hard, calcareous plates, 

 the solution No. II. is preferable. They vary in size from nncros- 

 copic minuteness to upwards of a yard in length. The larger and 



