He will be replaced by his Warriors clubmate, Moray Low.
Jon suffered a recurrence of a shoulder problem during training at St Pius College, Oxford Falls today, on Scotland’s last day in Sydney before they fly to Fiji tomorrow.
Scotland team doctor James Robson explained: “Jon has had problems with his shoulder and today during a relatively innocuous tackle technique exercise he sustained a shoulder subluxation, where the shoulder partially dislocated from the joint.
“We were able to put it back in but I believed it was appropriate care for Jon to be scanned and the scan showed that the shoulder had sustained damage incompatible with the demands of international rugby and sadly he will take no further part in the tour.
“He will be reassessed on return home with a view to possible surgery.”
Scotland head coach Andy Robinson said: “We are all disappointed for Jon who has trained well and been a popular member of the squad. We wish him a speedy recovery.
“We are now making arrangements for Moray to fly out and he will join us in Fiji early next week.”