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



furnished with a lead or tin vessel. This saved glycerine ; 

 but it was the gum that was so costly, on account of the 

 troubles in the Soudan. To economise as much as possible, 

 the fish were first dehydrated in spirit, so that the gum and 

 glycerine could be used over and over again. B is another 

 specimen of a very beautifully coloured wrasse. The spots 

 ought to be emerald green and the bands on the head violet.. 

 I have no doubt they would be, but I see by the label that it 

 was not placed at once in pure glycerine, but seems to have 

 been experimented with, how I do not recollect. I suppose, 

 seeing the colour fading, it was changed to pure glycerine, 

 but too late to save the more delicate tints. O is a star fish 

 prepared by the same process some years ago. But here the 

 usefulness of this process ends. Only very scaly fish, such 

 as sea perches and wrasses, and a few echinoderms, can be 

 prepared in this way. Ordinary fish, snakes, and frogs are 

 withered up by it out of all recognition, and rendered as 

 hard as iron. Was there any possibility of rendering the 

 specific gravity of the gum and glycerine less ? This was a 

 question to which I devoted myself for a long time. No 

 additions of watery solutions of any substances were of 

 avail. At last I found that by gently mixing with weak 

 spirit, briskly stirring all the time, that the gum, at first 

 precipitated in flocculent masses, was re-dissolved, and that 

 in that way solutions of almost any specific gravity could be 

 obtained. D is an extremely rare frog, presented by Mr. 

 Green, prepared and mounted in 1887 in gum and glycerine 

 reduced by spirit to the same specific gravity as milk. But 

 it is only very small specimens that can be mounted in this 

 way, the medium being too opaque for any larger bottles, 

 nor is it a good mounting medium even for them. The 

 specimen exhibited is in a very soft state. I could not allow 

 it to be handled, and hence it is useless for scientific 

 examination. The delicate violet tint of the large blotches 

 on the back, is, however, well preserved. If we attempt to 

 mount specimens preserved in this way in pure glycerine, they 

 are shrivelled up quite or almost as badly as if preserved with 



