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JOURNAL, R.A.S. (CEYLON). [VOL. XII. 



paste, or reduced gum and glycerine, a large proportion of 

 water, in addition to that naturally contained in them, and 

 consequently more than the carbolic acid could extract or 

 combine with, the result being that they had an atmosphere, 

 so to speak, of their own, which finally led to their more or 

 less speedy decay. Here is then a splendid medium for the 

 zoologist, especially in a hot climate. He is furnished with 

 a powerful and easily used preservative both for form and 

 colour which does not evaporate. N, the leg of a fly laid on 

 a glass slide in a drop of oil, and just simply covered by an 

 ordinary microscopic glass cover, has remained in the same 

 state for eighteen months. I need not say what a boon this 

 will be to the microscopist, who, whilst wishing to study 

 some subject, does not wish to mount his specimens perma- 

 nently. But with all these advantages it is of little use for 

 public exhibition, and I need scarcely say this was a great 

 disappointment to me. 



The spider question solved my difficulties (at least, I hope 

 so) once more. I noticed how exceedingly hard some spiders 

 had become in the oil, when it occurred to me that specimens 

 that had become so firm would resist the dehydrating action of 

 glycerine ; and that if spiders would, anything would. The 

 experiment was at once tried — the large rat snake, seven feet 

 long, some frogs, and the fish, coloured and uncoloured, will 

 show you with what success. 



The oil is also an admirable preservative for large fish 

 skins that can be mounted afterwards. They require no 

 varnishing, and retain much of their lustre, and a large sea 

 perch is exhibited prepared in this way. I have now merely 

 to read the recipe. Add carbolic acid to cocoanut oil till the 

 oil marks 10 to 20 degrees below proof on an hydrometer. 

 The more acid the more powerful the dehydrating effect, 

 and judgment must be used. In this climate it is best, 

 although not absolutely necessary, to remove the entrails. 

 Place the specimen, carefully wrapped in rag, in plenty 

 of this preparation. If wanted to mount for show, drain off 

 the superfluous oil and mount in glycerine. 



