Hooker George Turner joins Glasgow Warriors on a season-long loan from Pro12 rivals Edinburgh.
Scotland and Glasgow hooker Fraser Brown faces up to four months on the sidelines after ankle surgery.
Glasgow Warriors sign Tonga international prop Siosiua Halanukonuka from the Highlanders in New Zealand.
Fly-half Brandon Thomson is to sign a two-year contract with Glasgow Warriors after his loan spell from Stormers.
Audio & Video
Glasgow Warriors head coach Gregor Townsend looks back on some memorable moments as he prepares for his final match in charge.
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What's on BBC Sport this week
This week's sport on the BBC includes the World Aquatics Championships, England v South Africa in the third Test and the Challenge Cup semi-finals.