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On Mounting Ostracoda and Allied Genera in a Permanent 



Manner. 



By E. Gardner. 



Read October 22, 1875. 



I have been trying for a long time to mount the Ostracoda and 

 allied genera in a permanent manner, and having at last fancied 

 that I have succeeded, as my slides show no alteration after some 

 months, I beg to communicate my method, in the hope that other 

 young microscopists will improve upon it, and give the results of 

 their experience. I found that fluid media were of no use, as en- 

 dosmose, sooner or later, destroyed the objects, which do not admit 

 of being dried for mounting in resinous media. I therefore tried a 

 mixture of two-thirds gum arable and one-third syrup, made with 

 loaf-sugar with a few drops of alcohol and creosote and a little 

 corrosive sublimate. I found that a drop of this mixture hardened 

 sufficiently in about two days to imbed and preserve the object, and 

 to admit of the cell being filled up with gum dammar in benzole. 

 I use that prepared by White, of Litcham, in collapsible tubes. 

 Should the object show above, or project through the first coat of 

 gum when hardened, more must be dropped in, until it is quite 

 imbedded. The object is then covered with thin glass. My reason 

 for mixing the syrup with the gum arabic is merely to prevent the 

 gum from cracking or contracting too much when dry. 



