CHAPTER VI 



HOW TO MOUNT SPECIMENS 



The method of procedure in mounting specimens for study 

 varies according to the nature of the specimen, its preliminary 

 treatment, and the character of the mount to be made. As to 

 duration, mounts are either temporary or permanent. 



TEMPORARY MOUNTS 



In preparing a temporary mount, place the specimen in the 

 centre of a clean slide and add two or more drops of the tem- 

 porary mounting medium, which may be water, or a mixture 

 of equal parts of alcohol, glycerine, and water, or some micro- 

 chemical reagent, as weak Lugol's solution, solution of chloral 

 hydrate, etc. Cover this with a cover glass and press down 

 gently. Remove the excess of the mounting medium with a 

 piece of blotting paper. Now place the slide on the stage and 

 proceed to examine it. Such mounts can of course be used only 

 for short periods of study; and when the period of observation 

 is finished, the specimen should be removed and the shde washed, 

 or the shde washing may be deferred until a number of such 

 slides have accumulated. At any rate, when the mounting 

 medium dries, the specimen is no longer suitable for observation. 



PERMANENT MOUNTS 



Permanent mounts are prepared in much the same way as 

 temporary, but of course the mounting medium is dilTerent. 

 The kind of permanent mounting medium used depends upon 

 the previous treatment of the specimen. If the specimen has 

 been preserved in alcohol or glycerine and water, it is usually 

 mounted in glycerine jelly. If the specimen in question is a 

 powder, it is placed in the centre of the slide and a drop or two 



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