enough to immerse them directly in 70 per cent alcohol, re- 

 newing it when it becomes discolored. To avoid the contraction 

 of Halisarcidae, they should be fixed in chromic acid of 1 per 

 cent for about half an hour, or in saturated sublimate for 

 fifteen minutes. Those sponges which are to serve for study, 

 if they are not too large — that is, if they are not more than 

 10 cm. (4 inches) in diameter — are immersed in 90 per cent 

 alcohol or in absolute alcohol, which should be renewed after 

 three or four hours, and again after twenty-four to forty- 

 eight hours. If the 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 

 in 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 Anthozoan has been 

 caught is to place it in a receptacle with fresh sea water. It 

 always happens that these animals, when disturbed by the fish- 

 ing apparatus or transportation, contract or withdraw into 

 themselves completely. To cause them to expand, it is enough 

 to let them 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 No. 2, are used for preserving animals for muse- 

 ums and to some extent for the study of gross anatomy. 



Since all the Alcyonarians contain minute calcareous 

 spicules which furnish the specific characters, they shoud re- 

 main 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 Sympodium have become expanded, siphon off the water in the 



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