[a]Fig. 66.]—Rough Skeleton of a Small Animal. (After F.A. Lucas.)
12. The last thing is to make up the skeleton into a small, compact bundle, that will pack nicely and economically when dry, and withstand some pressure without breakage. Put the skull in the chest cavity. Fold up the upper joints of the legs, put the foot of each in the pelvis, and the other end in the cavity of the chest. Now tie all the legs tightly to the spinal column. (See Fig. 66.) Bend the tail under the pelvis and tie it fast also. Finally, hang the specimen up in the shade and wind, so that it will dry quickly.
It will be observed that the above process leaves the body of the skeleton entire, and all the bones of each leg and foot united by their natural ligaments. A skeleton prepared thus may ultimately be mounted as a "ligamentary skeleton," or it may be disjointed throughout, macerated, and mounted as a "disarticulate skeleton." Except for skeletons of bison, elk, and other animals which are entirely too large to admit of transporting their bodies whole, it is much the best to prepare all others in the field as described above, and disarticulate some of them afterward; for this reduces to a minimum the chance of losing some of the parts.
Skeletons of Large Mammals.—The process of roughing out the skeletons of large mammals, no matter how large they may be, is precisely the same as described above for small ones; but to make it possible to transport and box them, they must be cut to pieces, or, I had better say, disjointed, for fear some zealous partisan might interpret my words too literally, and go at a valuable skeleton with an axe. And right here let me publish a law which is as fixed and unalterable as the laws of the Medes and Persians, and admits of no exception:
In disarticulating a large skeleton, no matter how large, an axe or hatchet must never be used for any purpose whatever. Use nothing but the knife, and in a few cases a small saw to separate the sternum from the ends of the ribs.
To come down to the details of cutting up a large skeleton in, the field, and making it up into a number of separate bundles, let us suppose that the skeleton lies before us, completely roughed out, in accordance with previous advice. The bones of each leg must be dislocated (at the "knees" in ruminant animals) either once or twice, so that the parts can be easily handled. In a full-grown elephant the leg bones are so large it is necessary to cut the ligaments at each joint, so that the scapula, humerus, radius and ulna, and foot may each be handled separately.
Of course, the head is to be cut off at the first cervical vertebra. Then, by careful work, and much coaxing with the sharp point of the knife, dislocate the spinal column just where the neck joins the body. At first this will bother you, but have patience and you will soon learn how to do it easily and quickly. In dislocating the spinal column, take hold of the neck, move it backward and forward, and strain it a bit to see just where the articulating surfaces of the vertebral process are, so that you can cut them. When your intelligence has made some headway on the joint, then you may put forth a little main strength and tear the vertebræ apart, but do not attempt this too soon.
The next thing is to cut off the ribs, and the first step toward this is to cut out the sternum, or breastbone. (See Plate XX.) This so-called bone is really cartilage, soft enough in a fresh skeleton to cut on the outside, and in thin places, like cheese rind. It must be cut out in one piece, the same as may be seen in the figure of the mounted skeleton, and the dotted line A B shows where the cartilaginous ribs of the sternum join the bony ribs that form the main arch of the thorax. At the points marked by the dotted line, cut the two apart. I have never found it necessary to use a saw for this work in a perfectly fresh skeleton, but in dry ones a saw is necessary. When you come to the short, or "floating ribs," as they are called, it will be found that their cartilages are only attached weakly to the cartilages of the previous ribs, or else are altogether free. These must be cut from the ribs and preserved with great care.
After the ribs have been cut free from the sternum, separate them from the backbone, one by one, make them up into bundles, and tie them up. The pelvis is to be separated from the spinal column at the last lumbar vertebra; and if necessary the spinal column may be again dislocated about the middle.