Log-a-Log is the title given to the shrew leaders of the Guosim, Guoraf, and Guosssom. The Guosssom Log-a-Log holds the Blackstone as a mark of his title. Sometimes, they keep their given names, sometimes not. All Log-a-Logs have been male, with the exception of Grenn in Lord Brocktree.

"Log-a-Log" is a hereditary title, passed down throughout the generations. A family of shrews living on theGreat South Stream operated a ferry and assisted travelers in crossing the river aboard a floating tree trunk, or log. Shouting "Logalogalogalogalog" was the method of attracting the ferry shrew's attention.
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