This substance is a secretion obtained from several different animals,
notably the otter and muskrat. The glands which contain it are
located similarly to the castor glands of the beaver, and the musk
should be discharged into a vial, as previously described. The
musk of the female muskrat is said to be the most powerful, and
is chiefly used by trappers in the capture of that animal, the
otter being chiefly attracted by its own musk.