Alula

from WordNet (r) 3.0 (2006)

alula
    n 1: scalelike structure between the base of the wing and the
         halter of a two-winged fly [syn: {alula}, {calypter}]
    2: tuft of small stiff feathers on the first digit of a bird's
       wing [syn: {bastard wing}, {alula}, {spurious wing}]

from The Collaborative International Dictionary of English v.0.48

Alula \Al"u*la\, n. [NL., dim. of L. ala a wing.] (Zool.)
   A false or bastard wing. See under {Bastard}.
   [1913 Webster]