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treated. On short collecting trips the poisoning may be omitted, but if 
the bones are left for some time uncared for, insect larvae are apt to eat 
the ligaments and mix things up generally. 
Special Points Regarding Skeletons 
The bones of the hyoid apparatus should be carefully saved, but are 
generally lost by inexperienced collectors while removing the tongue. The 
hyoid bones are attached to the larynx and connect the windpipe with the 
base of the skull (Figure 52). 
Small bones, called sesamoids, are usually found embedded in the 
tendons where they ply over the under sides of the toes, and in other 
places, so the tendons should not be cut off close to the bone. There are 
often one or two small bones on the back lower part of the femur (thigh 
bone), and these should be left in place. Rabbits have a slender projec- 
tion extending backward at the lower end of the shoulder blade, and this 
should not be broken off. 
Figure 52. Hyoid bones of dog, with cartilages of larynx. 
The male organ of a great many mammals, such as seals, walrus, 
raccoon, and other carnivores, as well as beaver and many other rodents, 
is provided with a bone, the os penis, or baculum. In addition to being an 
integral part of a complete skeleton, this bone in some groups of mammals 
has diagnostic characters of generic significance. This bone does not 
articulate with the rest of the skeleton, but has ligamentary attachments, 
and should always be looked for. When found it should be left attached to 
the pelvic bones if possible, as it is easily lost. 
Cetaceans (Whales, Porpoises , etc.) 
The only satisfactory way devised for exhibiting the body appearance 
of cetaceans is by constructing a model from measurements and casts. Col- 
lecting the skeleton except for its size causes little difficulty. The slender 
