What is "ratitae"

Struthiones \Stru`thi*o"nes\, n. pl. [NL. See Struthio.] (Zo["o]l.)

1. A division, or order, of birds, including only the African ostriches.

2. In a wider sense, an extensive group of birds including the ostriches, cassowaries, emus, moas, and allied birds incapable of flight. In this sense it is equivalent to Ratit[ae], or Drom[ae]ognath[ae].

Ratitae \Ra*ti"t[ae]\ (r[.a]*t[imac]"t[-e]), n. pl. [NL., fr. L. ratis a raft; cf. L. ratitus marked with the figure of a raft.] (Zo["o]l.) An order of birds in which the wings are small, rudimentary, or absent, and the breastbone is destitute of a keel. The ostrich, emu, moa, and apteryx are examples.