[19] THE PRESERVATION OF MARINE ANIMALS HOVEY. 



per cent. After a few minutes this liquid should be poured off until 

 there is barely enough in the jar to cover the animals, which should 

 then be killed with cold saturated sublimate. 



Adamsia rondeleti is narcotized with tobacco smoke in the following 

 manner: Remove the hermit crabs from the shells on which the 

 actinias are growing and kill them in fresh water. Suspend the shells 

 by threads in beakers of sea water in which the actinias will have 

 ample room for expansion. The thread may be wound around the 

 shell or passed through a hole in it and then tied over a stick of wood 

 which rests on the edge of the beaker. Place one or more of the 

 beakers in a shallow tray (preferably with ilat bottom and x)erpendicu- 

 lar sides) containing a little water and cover with a bell glass. Fill 

 the bell glass by means of the bellows and pipe described on page 9, 

 being careful at the same time to insert a U-shaped piece of glass tub- 

 ing under the edge of the bell glass to permit the escape of the confined 

 air as the smoke is forced in. Avoid jarring the glasses containing the 

 actinias. 



To regulate properly the duration of the whole operation it is neces- 

 sary that the first fumigation should be made about 2 o'clock in the 

 afternoon. Little by little the smoke clears up and the water begins 

 to absorb the narcotizing substances contained therein and the animals 

 for the most part distend the corona of tentacles. About 5 o'clock a 

 second fumigation like the first should be made, and the objects are 

 allowed then to remain overnight. The following morning carefully 

 remove the bell jar and touch the tentacles with a needle to learn in 

 what condition of sensibility they are. If they do not contract under 

 this stimulus, place a small open beaker containing a few cubic centi- 

 meters of chloroform beside the jar containing the actinia and replace 

 the bell jar, allowing the fumes of the chloroform to work for two or 

 three hours. Lastly the animals are killed in the chrom-acetic mixture 

 No. 2, hardened with chromic acid of one-half per cent and placed in 

 weak alcohol and so on, where they are to remain suspended. If the 

 tentacles give signs of sensitiveness, make a third fumigation and 

 after a few hours test again. This is the only method which has 

 proved successful in obtaining specimens with the column well dis- 

 tended and with the disk and tentacles in full expansion. Cold 

 weather retards this and other narcotizing processes in a very marked 

 degree. 



Adamsia palUata can be prepared in the same manner without sus- 

 pension. Good results have also been obtained by narcotizing the 

 animal slowly with alcoholized sea water and then killing with the 

 chrom-acetic mixture No. 2, or with hot saturated sublimate. 



Cladactis, Gereactis, and the little Bunodeopsis strumosa are killed with 

 the chrom-acetic mixture No. 2, and immediately afterwards hardened 

 in chromic acid of 1 per cent. The first two should be suspended in 

 the hardening and the preserving fluids by means of a glass float, the 

 hook of which has been passed through the margin of the base. Before 



