These attendees were all transported to the Conference on Babel, with a formal reception held aboard the USS Enterprise. In all, a hundred and fourteen Federation delegates, of which thirty-two of were ambassadors. The last stop for picking up attendees was the planetVulcan.
James T. Kirk mentioned these delegates in his captain's log, noting that some of "the passengers [were] explosive." He further mentioned in a second log entry that "the Coridan system has been claimed by some of the races now aboard our ship as delegates, races who have strong personal reasons for keeping Coridan out of the Federation. The most pressing problem aboard the Enterprise is to make sure that open warfare does not break out among the delegates, before the conference begins." (TOS: "Journey to Babel")
The second revised final draft of the script, dated 19 September1967, makes the following notes about the below listed delegates: "...a number of Aliens in hall traffic."; "...other strange types in bright costumes. (The extent of this depends upon the budget... there should be enough variety to indicate an interplanetary representation.)"; "...as delegates pick up drinks, move to various conversational groups. There is a fantastic array of types from all cultures, some pleasant, some hostile."
These two alien delegates joined the USS Enterprise in 2268 to attend the Babel Conference. (TOS: "Journey to Babel")
According to the call sheet, these delegates were described as "Giants".
In the novel Forgotten History, these aliens were identified as Makusians from Makus III. In Star Trek Online, they were called Zambeans.
This Tellarite aide took part in the Babel Conference in the year 2268 and together with Gav represented his people. He was present when Gav initially confronted Sarek at the reception, regarding his vote for Coridan, but was notably absent when Gav confronted Sarek a second time, later at the same reception. (TOS: "Journey to Babel")
According to Blackburn, "There was another show there called "Journey to Babel". And that's where the Tellarites appear on the scene and they're pig-like. I played one of the creatures. All day long you've got the nose like this and you've got the overhead thing going over your eyes. So it was, like, all day long you're looking and you were seeing nothing but a nose." ("Billy Blackburn's Treasure Chest: Rare Home Movies and Special Memories" Part II)
According to the call sheet, this delegate was simply described as "Gav's aide".