BULLETIN 39, UNITED STATES NATIONAL MUSEUM [16] 



specimens are too large, small pieces may be cut off" and treated in this 

 manner. 



If they are to be dried, they should be washed first ii; fresh water for 

 a few hours, then they should lie for about a day in ordinary alcohol, 

 and then be placed in the air or in the sun. If treated in this way, 

 they will not have an offensive odor. If it is desired to retain the rosy 

 color of certain sponges {Suberites, Axinella) for several days, it is 

 enough to place them in 40 per cent alcohol and not change it. 



ANTHOZOA. 



The first thing to be done when an Authozoan has been caught is to 

 place it in a receptacle with fresh sea water. It always happens that 

 these animals, when disturbed by the fishing apparatus or transporta- 

 tion, contract or withdraw into themselves completely. To cause them 

 to expand, it is enough ti) let tliem remain in a jar with pure sea water, 

 although it may be necessary to keep them for a longer or shorter time 

 in running water. Many times it has been noticed that the water soon 

 becomes bad if it is not changed. 



The following methods, especially that with the chrom-acetic mixture 

 Ko. 2, a-e used for preserving animals for museums and to some extent 

 for the study of gross anatomy. 



Since all the Alcyonarians contain minute calcareous spicules which 

 furnish the specific characters, they should remain in the acid mixture 

 as short a time as possible so that the acid may not attack the spicules. 



In those cases in which chrom-acetic mixture No. 2 has not given 

 good results, a mixture of sublimate and acetic acid may be employed, 

 but always for the killing alone. The animals should be transferred 

 quickly to weak alcohol. 



A method used by G. von Koch is quickly to immerse the distended 

 animals in absolute alcohol or that of 90 per cent, making an injection 

 of the same afterwards into the interior of the animal. 



When the colonies of Cornularia, Clavularia, Rhizoxenia, and 8ym- 

 podium have become expanded, siphon off the water in the receptacle 

 until only enough remains to cover them. This operation should be 

 performed with great care to avoid any shock which could cause the 

 retraction of the tentacles. Then pour rapidly into the jar a volume 

 of chrom-acetic No. 2 double that of the water in which the animals 

 remain, and immediately afterwards transfer them to alcohol of from 

 35 to 50 per cent, giving the preparation a few gentle shakes to free the 

 tentacles and dispose them in natural manner. Another good method 

 of killing is with hot saturated sublimate, using the same proportions 

 as of the chrom-acetic mixture, and washing the animals when scarcely 

 dead in fresh water before the transfer to weak alcohol. 



The liSirge Alcyoniu7n is treated in the following manner: After the 

 rapid bath in chrom-acetic No. 2 it is suspended, scarcely dead, in ajar 

 containing weak alcohol in such a way that its tentacles do not touch the 



