Is it a huntsman horn?
http://cgi.ebay.com/9-1-2-Vintage-unmarked-Brass-Bugle-Fox-Hunting-Horn-/120749074909?pt=LH_DefaultDomain_0&hash=item1c1d34a9dd
Well, it does look like it could be, but curious mouthpiece. Possibly a type of reed mouthpiece.
Certainly looks similar to this one:
http://www.worthpoint.com/worthopedia/vintage-fox-hunting-horn-abercrombie-fitch
But certainly not the ‘usual mouthpiece’ as seen here:
http://www.gumtree.com/p/for-sale/2-vintage-copper-and-brass-brass-fox-hunting-horns/83472331
Even more curious- text lower down says it’s a hearing horn but sure doesn’t look like one to me.
I have that same horn and yes it is a reed horn and yes I have used it to hunt hounds. Not sure of it’s original purpose but it’s very handy to blow especially on a fast run because it’s simply easier to blow. I also like to strap it under one arm for quick use.
In case you didn’t read the description, it is a HEARING horn, used for deaf people.
"For sale is an antique brass medical ear horn for hearing purposes. Two piece ear horn unscrews at the plug showing its handmade engineering. No makes or marks found at all on this piece, but it does seem to amplify sound nicely. "
Sure is ugly.
Beverly already mentioned that it says in the description that it is a hearing horn. But, it also says in the title that it is a hunt horn.
Indeed, and we have a satisfied user of an identical horn confirming its utility.
I had never seen that type of mouthpiece before, have seen reed mouthpieces that seem to simply insert into a conventional brass horn.
I don’t understand. So is this an ear trumpet and hunting horn or just an antique horn? In one of the photos it looks like the reed mouthpiece is removed…and if it is th diameter of the horn is too big to use it as an ear trumpet. Or am I just not seeing something. (I’m on an iPad and am not wearing my glasses)
I have seen those sorts of reed mouthpieces before…and I want to say it was on antique instruments. On modern instruments it is housed within the mouthpiece.
The huntsman for our foot pack uses a reed horn. Much easier to blow when running after hounds.
It’s an interesting piece.
I’m sure the horn I have is not a hearing horn and it looks just like the one Alagirl posted for us. I looked at mine today and the only mark on mine is made in Italy. It is definitely an old horn & came to me via my mother who had lots of old treasures she’d collected over the years. It isn’t the prettiest sounding horn I’ve ever blown but it’s so handy and easy to blow.
Thanks, Maple Meadows. I went back and looked at your photo and they do appear to be similar.
So, this is an antique reed hunting horn, and not a hunting horn for the hearing impaired huntsman. 
Wonder how old it is. Too bad there is no provenance.
