What is "micrathene whitneyi"

Elf \Elf\ ([e^]lf), n.; pl. Elves ([e^]lvz). [AS. [ae]lf, ylf; akin to MHG. alp, G. alp nightmare, incubus, Icel. [=a]lfr elf, Sw. alf, elfva; cf. Skr. [.r]bhu skillful, artful, rabh to grasp. Cf. Auf, Oaf.]

1. An imaginary supernatural being, commonly a little sprite, much like a fairy; a mythological diminutive spirit, supposed to haunt hills and wild places, and generally represented as delighting in mischievous tricks.

   Every elf, and fairy sprite, Hop as light as bird from brier.
   --Shak.

2. A very diminutive person; a dwarf.

   Elf arrow, a flint arrowhead; -- so called by the English rural folk who often find these objects of prehistoric make in the fields and formerly attributed them to fairies; -- called also elf bolt, elf dart, and elf shot.

   Elf child, a child supposed to be left by elves, in room of one they had stolen. See Changeling.

   Elf fire, the ignis fatuus.
   --Brewer.

   Elf owl (Zo["o]l.), a small owl ( Micrathene Whitneyi) of Southern California and Arizona.