I have a similar small cow horn with the same scalloped end. There is a padded, cloth cover where a base plug would be and was use to store needles and pins. It is a hanging pin cushion.
It is an ornamental, decorative piece and I concur with TN LH as to it's having been, (or intended to be) a [pin cushion. Nice find, though a bit tattered. That can all be fixed, by the way.Thank you for bringing it in.Dickl
It's a bit hard to tell the exact scale of this horn from the photos. There's a possibility, especially having been found in Maine, that it could have been a form of sail-maker's horn. In the days of sailing ships, sailmakers, riggers and also common sailors and fishermen would sometimes have a horn configured such that it could be hung by the open end to hold the needed tools for rigging and sewing repairs (small fids, awls, marlinspikes, and sail needles) so the tools wouldn't go overboard during use on a rolling ship. When working on deck or aloft it could be worn around the neck to keep those tools accessable but hands-free. Horn was a good choice because leather scabbards didn't do well in constant saltwater exposure and the taper of the horn would slightly wedge-in a varied assortment of items in a way that wouldn't allow them to be easily spilled out. Like most personal effects, some of these were purely utilitarian and some were beautifully and intricately detailed; most probably fell somewhere in between. Just a thought.John
Wonder if it could have been set up on a stand or holder as a vase, Green would have been a good color for it. Tim C.