76 THE TAXIDERMIST'S GUIDE. 



brush. Much nicety is necessary in cleaning these, as their great 

 thinness renders them, in general, liable to be broken. A little Flor- 

 ence oil will improve the appearance of the epidermis and render 

 it less liable to crack. 



Land Shells seldom require any cleaning except washing in 

 water, as they are not liable to incrustations of any kind. 



When shells are perforated by marine animals, or otherwise 

 broken, if the specimen is rare, it is desirable to remedy these 

 defects as far as possible ; they may therefore be filled up, or 

 pieces added to them with the cement, which may be colored, 

 when dry, to its original state. 



OF POLISHING SHELLS. 



Many species of Marine and Fresh water Shells are composed 

 of mother-of-pearl, generally covered with a strong epidermis. 

 When it is wished to exhibit the external structure of shells, the 

 epidermis is removed and the outer testaceous coatings polished 

 down till the pearlaceous structure becomes visible. It has been 

 a common practice to remove the strong epidermis of shells by 

 means of strong acids, but this is a hazardous and tedious mode 

 of operating. The best method is to put the shells into a pan of 

 cold w r ater with a quantity of quicklime and boil it for two to four 

 hours, according to the thickness of the epidermis. The shells 

 afterwards must be gradually cooled, and some strong acid applied 

 to the epidermis, when it will easily peel off. Two hours are suf- 

 ficient for the common muscle being boiled. The shells are after- 

 wards polished with rotton-stone and oil, put on a piece of chamois 

 leather. 



The epidermis of the Uno Margaritifera is so thick that it 

 requires from four to five hours boiling. After the epidermis has 

 been removed, there is beneath it a thick layer of dull calcareous 

 matter which must be started off with a knife or other sharp 

 instrument ; this requires great labor, but, when accomplished, a 

 fine mother-of-pearl is exhibited which adds an agreeable variety 

 as a specimen. 



Various Turbos and Trochuses are also deprived of their epi- 

 dermis and polished with files, sand-paper, pumice-stone, &c. , till 

 the pearly appearance is obtained ; but all these modes are in- 

 vented for disfiguring rather than improving the shells in the eye 



