Townsend has selected a young 33-man squad, with an average age of 25 and just two players aged 30 or over.
Hooker McInally will lead his country in the absence of the rested John Barclay.
Luke Crosbie (knee), John Hardie (back), Huw Jones (wrist), Willem Nel (knee) and Hamish Watson (shoulder) miss out due to injury.
Forwards: Simon Berghan, Jamie Bhatti, Magnus Bradbury, Fraser Brown, Lewis Carmichael, Allan Dell, David Denton, Matt Fagerson, Zander Fagerson, Grant Gilchrist, Richie Gray, Luke Hamilton, Murray McCallum, Stuart McInally (captain), Jamie Ritchie, Tim Swinson, George Turner, Ben Toolis.
Backs: Nick Grigg, Chris Harris, Adam Hastings, Sam Hidalgo-Clyne, Alex Dunbar, Stuart Hogg, George Horne, Pete Horne, Ruaridh Jackson, Lee Jones, Blair Kinghorn, James Lang, Byron McGuigan, Ali Price, Duncan Taylor.
Tell us what you think about the Rugby World Cup and you could win £100