Both players finished the 2018/19 season in impressive form, which they continued into Saturday’s Guinness PRO14 final that ended in narrow defeat to Leinster at Celtic Park.
Townsend said: “We are fortunate to have a number of very good second-rows available to us right now. With Richie Gray, Tim Swinson and Andrew Davidson also in contention for this remaining place in our World Cup squad, Scott’s selection is a testament to how well he has performed throughout the season and in particular over the past few weeks.
“Scott has played very well in some crucial games for Glasgow and has really taken his game to the opposition. He was impressive in his ball carrying, defence and his all-round work-rate on Saturday against Leinster and we look forward to working with him and the other four second-rows in our squad.”
He added: “Kyle has made an excellent impact since his debut for Glasgow earlier this season and has displayed strong defensive capabilities as well as a providing go-forward for his team when carrying ball.
“His versatility is a bonus. He started out playing on the wing for Glasgow, has moved into the centre and has performed equally well in both roles.
“With every game he has looked more assured and, from our point of view, he will primarily be considered a winger who can cover the centre position. We have others in our squad that we view more as centre/wings but I’m sure over the course of the summer Kyle will get the opportunity to show what he can do in both positions.”
Former Kelvinside Academy pupil, Cummings (22) earned his first professional contract in 2016, having come through the Fosroc Scottish Rugby Academy system. He represented Scotland throughout the age-grades, captaining the U20 side in the 2015 World Championships in Manchester.
Steyn (25) has enjoyed a rapid rise in the past 12 months, first impressing for Scotland 7s in six world series tournaments before forcing his way into Glasgow Warriors’ backline, long before the one-year deal he signed for the 2019/20 season even started.
A former student at the University of Stellenbosch, South African-born Steyn (whose mother Gillian is from Glasgow) played in the Currie Cup for the Griquas and was named as the side’s captain for their 2018 campaign before joining up with the sevens side.
The inclusion of Cummings and Steyn takes the Glasgow Warriors contribution to the extended squad to 19, all of whom will now be given time off to rest before checking into camp next month.
Watch: Gregor Townsend talks about his initial 42-man Scotland World Cup squad
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