The 6'8" 24-year-old made his international debut last season and has since gone on to win seven Scottish caps.
All 38 players now face two intense phases of preparation for the game's glittering global showcase to be hosted mainly in France in September and October but with matches also taking place in Scotland and Wales.
Scotland head coach Frank Hadden explained: "This week most of the players are embarking on a five-week fitness, strength and conditioning camp, under the direction of our fitness coach, Mark Bitcon.
"Phase two will see the emphasis very much on rugby and will lead into our Bank of Scotland Corporate August Tests against Ireland and South Africa. Our intention is to make this the best prepared and fittest Scotland squad ever for a Rugby World Cup."
Under RWC tournament regulations all teams are scheduled to declare their 30-man final squads by mid August.
Hadden has selected five uncapped players in the squad, with 27-year-old centre Calum MacRae; prop Alasdair Dickinson and centre/wing Nick De Luca, both 23; wing Thom Evans, 22; and 20-year-old openside flanker John Barclay all included.
They are joined by 19 other players for whom a Rugby World Cup would be a new experience.
"The Barclays Churchill Cup proved most useful in helping us to determine the final make-up of our World Cup training squad. In total some 13 players who were involved in that competition with Scotland A have won selection for this squad."
Hadden added: "I am monitoring the progress of our winger Simon Danielli. The groin injury he sustained against Ireland A on Saturday does not appear to be as bad as first thought and he will be subject to further assessment when he returns from holiday."
Scotland Rugby World Cup Training Squad
Mike Blair (Edinburgh Rugby)*, Chris Cusiter (Border Reivers)*, Nick De Luca (Border Reivers), Rob Dewey (Edinburgh Rugby), Marcus Di Rollo (Edinburgh Rugby), Thom Evans (Glasgow Warriors), Andrew Henderson (Glasgow Warriors), Rory Lamont (Glasgow Warriors), Sean Lamont (Northampton Saints), Rory Lawson (Gloucester)*, Calum MacRae (Border Reivers)*, Graeme Morrison (Glasgow Warriors), Dan Parks (Glasgow Warriors), Chris Paterson (Edinburgh Rugby), Gordon Ross (Castres), Hugo Southwell (Edinburgh Rugby), Nikki Walker (The Ospreys), Simon Webster (Edinburgh Rugby)
John Barclay (Glasgow Warriors)*, Kelly Brown (Border Reivers)*, Dave Callam (Edinburgh Rugby)*, Alasdair Dickinson (Edinburgh Rugby)*, Ross Ford (Border Reivers)*, Dougie Hall (Edinburgh Rugby), Jim Hamilton (Leicester Tigers), Nathan Hines (Perpignan), Allister Hogg (Edinburgh Rugby)*, Allan Jacobsen (Edinburgh Rugby), Alastair Kellock (Glasgow Warriors)*, Gavin Kerr (Border Reivers), Scott Lawson (Glasgow Warriors)*, Scott MacLeod (Llanelli Scarlets), Euan Murray (Glasgow Warriors), Scott Murray (Edinburgh Rugby), Craig Smith (Edinburgh Rugby), Alasdair Strokosch (Edinburgh Rugby)*, Simon Taylor (Edinburgh Rugby)*, Jason White (Sale Sharks)
* = Member of Scottish Institute of Sport
Not considered due to injury: Simon Danielli (Border Reivers)