1888 G. Rolleston & W. H. Jackson (ed. 2) 91 Anteriorly to the septum is a large bone, the ecto-ethmoid..(= the pre-frontal of Huxley).
1928 C. F. Cooper (ed. 4) II. 78 The outer walls of the olfactory capsules may be ossified by paired ecto-ethmoids.