in weak alcohol by means of a thread fastened around the column 

 near the base. A few gentle shakes may be needed to adjust the 

 tentacles. It is not necessary to suspend the small specimens. 



Actinia equina and A. cari are treated with boiling mix- 

 ture of sublimate and acetic acid, followed by chromic acid of 

 one-half of 1 per cent for hardening. Frequently success has 

 been attained with the first of these species by lifting it 

 gently with a spatula from the beaker in which it is expanded 

 and immersing it in a saturated solution of sublimate. 



Edwardsia is slowly narcotized by dropping from time to 

 time a few drops of 70 per cent alcohol into the sea water in 

 which it is. It is then killed with hot saturated sublimate. 

 Success depends upon the complete loss of sensitiveness, which 

 may be tested by touching the tentacles with a needle point. 



Certain species of Polythoa are very difficult to pre- 

 pare. Even with reagents of rapid action they will have the 

 body well distended and often only a portion of the tentacles 

 outside the disk. One species which lives in sponges and among 

 calcareons algae (probably a variety of P. axinellae) is pre- 

 pared very successfully with boiling saturated sublimate. 



Larvae of the Actinians are killed with saturated subli- 

 mate or with chrom-acetic No. 2. 



Madreporaria 



Astroides calycularis is allowed to remain overnight 

 in a beaker filled with clear sea water. The following morn- 

 ing usually shows the polyps in full distension. Then, after 

 turning off a portion of the water (enough to leave the animals 

 barely covered) , kill them with a solution of boiling sublimate 

 and acetic acid in volume equal to that of the sea water, and 

 immediately afterwards transfer the colony to 35 per cent alcohol, 

 making an injection of the alcohol into each polyp to keep it 

 well distended. At each change of alcohol up to 70 per cent 

 make a similar injection, and be sure to test the final solu- 

 tion with tincture of iodine to see that the sublimate has been 

 eliminated. 



Caryophyllia, Dendrophyllia, and Cladocora are fixed with 

 boiling saturated sublimate, but it is very difficult to prepare 

 them with the polyps in perfect expansion on account of their 

 great contractility and also by reason of the extreme delicacy 

 of their walls. 



Hy dr ome du s ae 



The Hydromedusae in general are very delicate forms, which 

 are easily injured and which quickly decompose, hence it is 



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