BULLETIN 39, UNITED STATES NATIONAL MUSEUM. [32] 



sea water. The hardening is done in the long wax-bottomed trays 

 with 70 per cent alcohol, straightening out the animals and lioldiiig 

 them in place when necessary by means of wooden pins. After a iew 

 hours in the tray, they should be put into tubes and allowed to rest in 

 a horizontal position for a day or so. Since 70 per cent alcohol does 

 not penetrate the tissues of these animals well enough to prevent 

 maceration, 90 per cent alcohol must be used for permanent preserva- 

 tion. Large specimens should be suspended in the tube by means of a 

 thread attached to a float. 



The method just described has given good results with annelids 

 belonging to the following families: Polygordiidse, Opheliadse, Capitel- 

 lidse, Telethusidfe, Maldanidse, Ariciidse, Cirratulidse, Spionidse, Tere- 

 bellidse, with the excejjtion of the genera Polymnia and Lanice, which 

 are killed with the mixture of sublimate and chromic acid; among the 

 Aphroditidse certain Poly noinse, and all the Sigalioninae; the Aniphi- 

 nomidae, which can also be well treated with saturated sublimate; 

 among the Eunicidse, the Stg^urocephalinse, Lysaretinae, and Lumbri- 

 conereinse ; all the Nereidse, Glyceridse, Syllidse, Hesionidae, and Phyl- 

 lodocidse. 



In the family of the ChlorhsemideB the genera Stylarioides and Tro- 

 phonia are narcotized with alcoholized sea water, hardened in chromic 

 acid of 1 per cent, and transferred to alcohol. Siiilionostomum diplo- 

 eJiaitos of the same family is killed in a solution of chloral hydrate of 5 

 per cent, and after hardening for fifteen minutes in 1 per cent chromic 

 acid is transferred to alcohol. Another good method is to use the sul- 

 phate of copper and sublimate mixture for killing, allowing the animals 

 to remain five minutes in the solution. Animals of this species, when 

 treated with the ordinary reagents, break to pieces with the greatest 

 ease. 



Hermionidse are immersed directly in 70 per cent alcohol (old solution 

 will do), taking care that the animals do not die in a curved position. 



Chfetopteridae, Sternaspidse, the large SpirograpMs and the large 

 Serjoulinas of the genus Frotula are killed in 1 per cent chromic acid, 

 where they are allowed to rest at least half an hour. Then after 

 thorough washing in fresh water, they are put into alcohol of 70 per 

 cent, and afterwards into that of 90 per cent. SpirograpMs can not be 

 well treated in its tube or be returned to it after treatment. Myxicola 

 infundihulum is killed in saturated sublimate, and, after ten or fifteen 

 minutes, thoroughly washed and put into 50 per cent alcohol for a few 

 hours before it is put permanently into that of 70 per cent. 



The following annelids are killed with cold saturated sublimate, in 



which they should not be allowed to remain more than fifteen minutes; 



all the Amphictenidse (which may be placed in alcoholized sea water 



^til well out of their tubes), the Hermellidse, the Serpulidse (some of 



.^hich should remain for some hours in a 0.1 of 1 per cent solution of 



chloral, so that they may come wholly or partly out of their tubes), of the 



