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 Sept., 1914 A METHOD OF CLEANING SKULLS 241 stream of water will clean the bones if they are first placed on a fine-meshed screen. Notes.--Dry flesh requires less cooking than fresh. If practicable, dry before cooking. In shipping undried skeletons dry cornmeal, in quantity, will keep the meat from becoming putreseent. Sheep, deer, and goat skeletons are so easily cleaned after cooking for considerable time in water alone that no solution should be used. Cleaning skulls.---The individual age of the skulls, as well as the genus, has much to do with the length of time they should be stewed. The skull of an adult Peromyscus will not be injured by a process which would disarticulate the skull of a juvenile Neotoma. It is necessary, therefore, to group each genus by itself; and in one genus to separate the adults from the juveniles. The next step should be the removal of the brains. This should always be done in the field while the skull is still fresh, as it can then be done with greatest ease and least danger of injuring the bones. If this has been neg- lected the skulls should be thoroughly soaked in warmed water and the brains removed with a bent wire or a small scraper (such as is figured in Hornaday's "Taxidermy"). A half ounce "infant rectal" syringe is also very useful. The nozzle should be filed down until it is thin-walled so that it may be inserted in the foramen magnum of a small skull. By holding the barrel of the syringe between the second and third fingers of the right hand, close to the palm, n9z- zle facing outward, and the ring of the plunger over the first joint of the thumb, one hand can operate the syringe while the other holds the skull under water. Care should be taken when water is forced into the brain-case, or the bones will be wrenched apart. If the brain is thoroughly softened and broken up, the greater part of it can be sucked out, instead of being forced out. If this is done there will be no danger of disarticulating the posterior portion of the skull. If the brains are not removed before cooking, they may expand and force the brain-case apart. If each skull has a heavy, non-soluble tag attached, with the number or identifying mark written thereon with waterproof ink, many skulls may be cooked loose in one container. Higgins' Eternal Ink on imitation parchment paper has been used with success. Each group of slulls should be placed in separate, clean, unrusted granite-ware or aluminum pots and covered with Solution I. These should be cooked as. directed for skeletons, trying several skulls at'short intervals to observe progress. As soon as done, wash, cook in water, then in Solution II and finally clean. All clinging flesh should be removed by using a bone scraper (not too large), a tooth brush (previously dampened to soften it), and the syringe. With the exception of the juvenile skulls, which can not be cooked so long, it will be found that the meat will become so softened as to be readily sucked off by using the syringe as directed for the brains. Some experimenting may be found necessary in adopting this method, but it should not prove difficult to master, as these directions have been used in manuscript form by persons without previous experience or personal instruc- tion. This process has been employed in the osteological laboratory of the Cali- fornia nseum of Vertebrate Zoology for the Past four years, and many thous- ands of skulls' and many hundreds of skeletons have been prepared, all with uniformly satisfactory results. University of California, August 7,