These figures are called a variety of names, including half dolls, teepuppen (tea dolls), demi figurine (half figurine), pin dolls and telephone dolls. These particular dolls are chalk or composition, covered with wax. I use the term "wax over." You can find half doll telephone covers, tea cozies, lamps/nightlights, brush and powder puff toppers, pin cushions, and other novelty items. They are also turned into complete dolls with arms and legs. They've been used on candy box and powder box lids and more.
Here are a few examples of wax over half dolls, courtesy of Lynda Wake.
