The Collaborative International Dictionary of English v.0.48:

Longtail \Long"tail`\, n.
   An animal, particularly a log, having an uncut tail. Cf.
   Curtail. Dog.
   [1913 Webster]

   Note: A longtail was a gentleman's dog, or the dog of one
         qualified to bunt, other dogs being required to have
         their tails cut.
         [1913 Webster]

   Cut and longtail, all, gentlefolks and others, as they
      might come. --Shak.
      [1913 Webster]