TREATMENT OF THE SKINS OF SMALL MAMMALS. 29 



nor alcohol (unless it be of great strength) can strike through a 

 thick layer of flesh and penetrate through the skin to the epi- 

 dermis quickly enough to save it from decomposition. The 

 epidermis of most animals is of such a close and oily nature 

 that preservatives cannot strike through it from without, and 

 therefore when a skin is removed it must be cleaned of flesh 

 and fat, so that the preservative liquid or dry powder can come 

 immediately in contact with the cutis. 



The skin is now off. If the lips have been opened out, the 

 ears skinned to the tip (if they be haired), and the" feet well 

 skinned down, we are ready to go on. But first we must clean 

 the skull. Cut the flesh all off, or the most of it at least, for it 

 is not possible to get it all away at the base ; cut out the eyes 

 and tongue, and with your brain-hook, or a piece of wire ham- 

 mered flat at the end and bent up at a right angle, patiently 

 draw out the brain through the occipital opening at the base 

 of the skull. By this time, perhaps, the skin will be bloody in 

 places, or possibly it was dirty to start with. Now is the time 

 to wash it thoroughly in clear water. Remember that a skin 

 which has been dried with blood upon it is damaged forever. 

 It stains the hair, and very often forms a hard, gummy mass 

 which nothing will dissolve. 



PRESERVATION OF THE SKIN. The next step depends upon what 

 you propose to do with the skin, or it may depend upon the 

 conditions under which you are collecting. 1. If you are in 

 your laboratory preparing skins to mount, preserve them all 

 (except quite young specimens and certain others) in a soft, or 

 wet state, in a salt-and-alum bath. 2. If you are in the field 

 (especially the tropics), making a large collection of mammal 

 skins for mounting, by all means do the same if possible. 3. 

 If the skins are for purposes of study as skins, during which fre- 

 quent handling and examination is absolutely necessary, make 

 them up as dry skins. 4. If you lack facilities for preserving 

 them wet, then make dry skins of them. 5. If the necessities 

 of travel and transportation make it necessary to reduce the 

 weight to the lowest possible limit, and to divide it up for car- 

 riage overland, make up all skins dry, both little and big. 6. 

 If you have only one or two skins to preserve, it will be less 

 trouble to you to make them up dry at once. 



