Sixteen Glasgow Warriors are included in the squad - Ryan Grant, Gordon Reid, Fraser Brown, Jonny Gray, Tim Swinson, Josh Strauss, Ryan Wilson, Henry Pyrgos, Finn Russell, Duncan Weir, Mark Bennett, Peter Horne, Richie Vernon, Sean Lamont, Tommy Seymour and Stuart Hogg.
South Africa-born Josh Strauss will qualify to play for Scotland under residency rules shortly before the tournament, while Tim Swinson has recovered from injury just in time to be included.
Greig Laidlaw continues as skipper.
Cotter said: "We’re very pleased to name the 31 and we’re confident these players will represent Scotland well in the Rugby World Cup.
“It’s been a tough but rewarding two months. We’re proud of the effort everyone has put in to this point.
“Getting down to 31 has been a difficult process because all the players have represented themselves well in the opportunities given.
“There are some good players and good people who haven’t made it. We obviously feel for them and would like to thank them for all their efforts, however we must now move forward to our last preparation match against France before embarking on our Rugby World Cup campaign.”
SCOTLAND SQUAD: RUGBY WORLD CUP 2015
PROPS
Alasdair Dickinson (Edinburgh Rugby); 46 caps; 4 RWC appearances (2007 & 2011)
Ryan Grant (Glasgow Warriors); 23 caps
Gordon Reid (Glasgow Warriors); 11 caps
Willem Nel (Edinburgh Rugby); 2 caps
Jon Welsh (Newcastle Falcons); 6 caps
HOOKERS
Fraser Brown (Glasgow Warriors); 9 caps
Ross Ford (Edinburgh Rugby); 88 caps, 8 RWC appearances (2007 & 2011)
Stuart McInally (Edinburgh Rugby); 2 caps
SECOND–ROW
Grant Gilchrist (Edinburgh Rugby); 10 caps
Jonny Gray (Glasgow Warriors); 14 caps
Richie Gray (Castres); 45 caps; 4 RWC appearances (2011)
Tim Swinson (Glasgow Warriors); 12 caps
BACK–ROW
David Denton (Edinburgh Rugby); 27 caps
John Hardie (Unattached); 1 cap
Josh Strauss (Glasgow Warriors); uncapped
Alasdair Strokosch (Perpignan); 45 caps; 3 RWC appearances (2011)
Ryan Wilson (Glasgow Warriors); 10 caps
SCRUM–HALF
Sam Hidalgo-Clyne (Edinburgh Rugby); 7 caps
Greig Laidlaw CAPTAIN (Gloucester); 40 caps
Henry Pyrgos (Glasgow Warriors); 16 caps
STAND–OFF
Finn Russell (Glasgow Warriors); 10 caps
Duncan Weir (Glasgow Warriors); 19 caps
CENTRE
Mark Bennett (Glasgow Warriors); 8 caps
Peter Horne (Glasgow Warriors); 10 caps
Matt Scott (Edinburgh Rugby); 28 caps
Richie Vernon (Glasgow Warriors); 22 caps, 3 RWC appearances (2011)
WING
Sean Lamont (Glasgow Warriors); 96 caps, 8 RWC appearances (2007 & 2011)
Sean Maitland (London Irish); 15 caps
Tommy Seymour (Glasgow Warriors); 17 caps
Tim Visser (Harlequins); 20 caps
FULL–BACK
Stuart Hogg (Glasgow Warriors); 33 caps
SCOTLAND MATCH SCHEDULE
Summer Tests:
Ireland 28-22 Scotland, Aviva Stadium, Dublin
Italy 12-16 Scotland, Stadio Olympico, Turin
Scotland 48-7 Italy, BT Murrayfield, Edinburgh
Saturday 5 September: France v Scotland, Stade de France (ko 8.00pm BST) – live on BT Sport
RWC 2015 Pool stages:
Wednesday 23 September: Scotland v Japan, Kingsholm (ko 2.30pm)
Sunday 27 September: Scotland v USA, Elland Road (ko 2.30pm)
Saturday 3 October: South Africa v Scotland, St James’ Park (ko 4.45pm)
Saturday 10 October: Samoa v Scotland, St James’ Park (ko 2.30pm)