1 882.] in the Zoological Station in Naples. 705 



saturated by it. In order to kill more quickly than can some- 

 times be done at the ordinary temperature, the solution is heated, 

 and in very difficult cases may be used boiling. 



Corrosive sublimate has been used with success by Dr. Lang 

 and others in the following cases : Hydroids, corals, Nemertines, 

 Gephyrea, Balanoglossus, Echinoderms, Sagitta, Annelids, Rhab- 

 docoela, Dendrocoela, Cestodes, Trematodes, embryos and adult 

 tissues of Vertebrates and, according to Mayer and Giesbrecht, 

 Crustacea with thin chitinous envelopes, e. g., Sapphirina, Cope- 

 pods and larvae of Decapods. , 



The two great advantages of Dr. Lang's method are, (1) that 

 animals so treated are easily stained, and (2) they are killed so 

 quickly that they are left, in most cases, in a fully extended con- 

 dition. Hot corrosive sublimate kills leeches so instantaneously 

 that they often remain in the attitude assumed the moment before 

 the fluid is poured over them. The color, however, is not so 

 well preserved as when killed with alcohol, or even with weak 

 chromic acid. 



It should be remembered that objects lying in a solution of 



ments ; wood, glass or platinum may be used. 



9. Dr. Andres' Methods of beating Actinic?.— Among the vari- 

 ous methods employed by Dr. Andres in killing the Actiniae, the 

 three following, given in the order of their excellence, are said to 

 have worked most satisfactorily : 



A. Corrosive sublimate. — •With small animals a hot solution, used 

 in the manner recommended by Dr. Lang, gives good results ; 

 with larger animals, where this mode of treatment fails, the fluid 

 must be injected. The cannula of a glass syringe, filled with the 

 hot fluid, is inserted into the mouth at the moment it opens, 

 which act habitually follows on gently touching the lip. After 

 injecting, the hot solution is poured into the glass containing the 

 animal and a small quantity of sea water. 1 



If the operation is cleverly performed, the animal remains fully- 

 expanded, as the mechanical pressure of the injected fluid pre- 

 vents contraction. 



After from five to fifteen minutes the animal is washed in dis- 

 tilled water and allowed to remain twelve hours in 50 per cent. 



Andres. " Intorno all'Edwardsia Claparedii," in the Proceedings of the " Reale 



