The Collaborative International Dictionary of English v.0.48:

Firlot \Fir"lot\, n. [Scot., the fourth part of a boll of grain,
   from a word equiv. to E. four + lot part, portion. See
   Firkin.]
   A dry measure formerly used in Scotland; the fourth part of a
   boll of grain or meal. The Linlithgow wheat firlot was to the
   imperial bushel as 998 to 1000; the barley firlot as 1456 to
   1000. --Brande & C.
   [1913 Webster]