orgyia leucostigma

from The Collaborative International Dictionary of English v.0.48

Orgyia \Or*gy"i*a\, prop. n. [NL., fr. Gr. ? the length of the
   outstretched arms. So named because, when at rest, it
   stretches forward its fore legs like arms.] (Zool.).
   A genus of bombycid moths whose caterpillars (esp. those of
   {Orgyia leucostigma}) are often very injurious to fruit trees
   and shade trees. The female is wingless. Called also {vaporer
   moth}.
   [1913 Webster]