These are also called "lap pipes" (because of how you smoke them). The carvings most frequently feature animals, battles, and pastoral scenes. They're frequently dated... and the dates are always wrong! The meerschaum pipe industry didn't get started until the middle of the 1800s. These pipes came in around the 1890s, and were sold inexpensively as being "antique-style." They were given dye jobs (though high-end meerschaums were, too). Oh, and... they were nearly always pressed ("chip") meerschaum.
If you have access to one of the old Sears catalog reprints from the late 1800s-early 1900s, there's usually one in the pipes section.