Well, with no idea as to the size, it's hard to even guess.
It looks like a "funnel" for sound, doesn't it? Like an old ear trumpet, or megaphone, or something to do with early audio recording (think of the fuzzy microphones you see today, used to muffle wind and breath sounds).
Is it metal or bakelite? That might be a clue.
Anyhow, until someone smart comes along to help, you might poke around on the web along those lines, assuming the size warrants such searches. (For all I know, the thing may be only three inches long).
