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thriving, and continue to rapidly clean any skull or skeleton, provided, of 
course, food in the form of dried meat has been furnished when uncleaned 
skulls or skeletons were not on hand. After taking the bones from the beetle 
can, they were soaked with ammonia and water essentially as in the method 
described by Hall and Russell. Upon removal from the water any small bits 
of tissue remaining were easily separated with a scalpel or brush. Glass jars 
or clean, new tin cans should be used for soaking bones; otherwise they 
may be stained. As low temperatures make the beetles and larva? inactive, 
and because vibrations are disturbing to them, it is desirable that they be 
kept in a warm, quiet place. 
The M. V. Z. Method of Cleaning Large Skulls and Bones. Although 
the routine practice at the Museum of Vertebrate Zoology is to use 
dermestid beetles in removing flesh from small skulls, Hall and Russell 
(1933) state that experience has shown that it is better to “cook” skeletons 
as large as deer, moose, and mountain lion instead of “bugging” them. 
When skulls are to be cooked, it is best to soak them first for 12 hours 
in a solution of water and ammonia (proportion, 2 quarts of water to an 
ounce of ammonia). In cooking, 1 tablespoonful of mild soap flakes and 
15 cc. of concentrated ammonia are used to 2 or 3 quarts of water. This 
solution is brought to near the boiling point and cooked (“simmered”, not 
“boiled”) until the meat is soft and transparent. To remove the meat, a 
fine stream of condensed air is far superior to instruments or water. Also 
it is more thorough and the loss of lachrymals and zygomatic arches is 
greatly reduced for the reason that these parts are more easily displaced 
by touch of an instrument than by the air. The air, strangely enough, does 
not blow off these fragile bones even when striking them with considerable 
force. One must be careful, however, to keep a finger over the teeth, for 
there is danger of blowing them out in the case of those specimens that 
have been cooked. The cavities of large leg bones are filled with marrow, 
which must be eliminated as soon as possible to prevent it from soaking 
into the bones and staining them. If a small hole is drilled in each end of 
the bones at the time of cooking, the water will loosen the marrow and it 
can be blown out with compressed air. Even though the skeleton may have 
been roughed out well, there is enough oil in the remaining meat thoroughly 
to soak the bone, if it be allowed to remain uncleaned for as long a time 
as is required for the bugs to clean it. The soaking of large skulls and 
skeletons in many changes of water will remove the blood. Although it is 
usually impossible to soak them in the field, opportunity should be taken 
to soak such specimens as arrive at the laboratory in a fresh condition. 
Never use water that is hot; this will set the blood in the bone. (In the 
northern woods and mountains it is usually practicable to put large skulls 
and bones in gunny sacks and immerse them in a brook or pond over night.) 
Degreasing Bones 
Degreasing is done by placing the bones in carbon tetrachloride, 
benzine, or pure gasoline in glass jars and leaving them in the sunshine 
until the grease is dissolved. If benzine or gasoline is used, a false bottom 
of wood is fitted into the jar, so that the bones will not lie in the grease 
that soaks out of them. Benzine and gasoline are inflammable and 
explosive, and some cheap grades of gasoline contain a gummy substance 
