BULLEllN 39, UNITED STA.TES NATIONAL MUSEUM. [10] 



may be shipped iu auy strong, light box. Wrap each one separately in 

 a thin sheet of cotton, and pack closely and smoothly. In tropical 

 countries, to lessen danger from attacks of insects, skins should not be 

 boxed until ready to ship; and frequent examination for beetles and 

 their young should be made. 



Slight variations in the details of the foregoing directions will natu- 

 rally suggest themselves. They need no special remark here. Some 

 dilBculty, however, may be found in preparing the skins of bats. These 

 animals are to be skinned exactly as directed, except that the bones of 

 the legs and wings must never be removed. Insert wires into the legs 

 and wings. Fold the wings of bats close to the sides of the hody, bending 

 the wire forward at the elbow. Lay the skin in the position shown in 

 the illustration. Bat skins from all localities are much needed. At 

 least one-half of every series should be preserved in this way; the 

 remainder may be kept in alcohol or formalin. 



SKELETONS. 



To prepare skeletons of small mammals in the field, remove the skin 

 as already directed, but cut through the skin itself at ankles and wrists, 

 leaving the feet attached to the legs. Then remove the viscera and 

 larger muscle masses, but not enough to disjoint any part of the body. 

 Make up the skin roughly and preserve it as an aid to identification. 

 Dry the skeleton quickly and thoroughly. 



SPECIMENS IN ALCOHOL OR FORMALIN. 



Alcohol and formalin are not used at their full strength. Add to 

 commercial alcohol (95 percent) one-fifth its volume of water. Add to 

 commercial formalin' twenty times its volume of water. Label specimens 

 with pencil or waterproof ink on s^i^ j9fy:>er (not x)asteboard). Open 

 the abdominal cavity so that preservative fluid may penetrate freely, 

 but do not remove any of the viscera. Wet the fur thoroughly to base 

 with water or alcohol before specimens are placed in formalin. At first 

 keep specimens covered by at least double their volume of fluid. Less 

 is required after they are thoroughly preserved. Specimens that have 

 been preserved for several weeks may be safely shipped in air-tight 

 jars, tanks, or bladders, if wrapped (to prevent abrasion) in cloth, tow, 

 or cotton batting, dampened with the preservative fluid. 



In tropical countries where formalin may not be obtainable, and alco- 

 hol, if to be had at all, is very expensive, cane rum may be used as a 

 substitute, though specimens preserved in it should be transferred to 

 alcohol or formalin for permanent storage. Only the strongest grades 

 of rum should be used. 



^This is a 40 percent (saturated) aqueous solution of formaldebycle gas. It is 

 sometimes sold under the name formaldehyde. 



