Adam Hastings and Huw Jones will miss Scotland's summer tour to South America because of injury.
Gloucester fly-half Hastings has withdrawn from the squad with a hamstring problem while Harlequins back Jones is out with a back injury.
In the forward pack, uncapped Glasgow hooker Jonny Matthews has been given his first call-up.
Captain Stuart Hogg and Finn Russell are not part of the squad, having been rested by head coach Gregor Townsend.
After Scotland 'A' face Chile in Santiago on 25 June, Townsend's men have a three-match Test series with Argentina on 2, 9 and 16 July.
Scotland squad
Forwards: Ewan Ashman (Sale), Jamie Bhatti (Glasgow), Magnus Bradbury (Edinburgh), Dave Cherry (Edinburgh), Andy Christie (Saracens), Luke Crosbie (Edinburgh), Scott Cummings (Glasgow), Rory Darge (Glasgow), Matt Fagerson (Glasgow), Zander Fagerson (Glasgow), Grant Gilchrist (Edinburgh), Jonny Gray (Exeter), Jamie Hodgson (Edinburgh), Ben Muncaster, Pierre Schoeman (both Edinburgh), Javan Sebastian (Scarlets), Sam Skinner (Exeter), Rory Sutherland (Worcester), George Turner (Glasgow), Murphy Walker (Glasgow), Hamish Watson (Edinburgh), Glen Young (Edinburgh), Jonny Matthews (Glasgow)
Backs: Mark Bennett, Matt Currie, Darcy Graham (all Edinburgh), George Horne (Glasgow), Damian Hoyland (Edinburgh), Rory Hutchinson (Northampton), Sam Johnson (Glasgow), Blair Kinghorn (Edinburgh), Rufus McLean, Ali Price (both Glasgow), Kyle Rowe (London Irish), Ollie Smith, Ross Thompson, Sione Tuipulotu (all Glasgow), Duhan van der Merwe (Worcester), Ben White (London Irish)