This genus is, in the Catalogue of Birds, placed in a section with somewhat
long tarsus, the latter being longer than the culmen, containing in
addition to _Prosobonia_ the genera _Tringites_, and _Aechmorhynchus_ (see
afterwards), and it differs from the latter by its long hind toe, from the
former by its square tail. The position of this singular bird is, however,
not quite certain. The late Henry Seebohm placed it in the genus
_Phegornis_, though the latter has no hind toe whatever, and it has
even--but doubtless wrongly--been suggested that it belonged to the
_Rallidae_, rather than to the _Charadriidae_. We know only one species. It
is true that Dr. Sharpe bestowed a new name on the figure of Ellis, which
is said to have been taken from an Eimeo-specimen, but it is hardly
creditable that it belongs to a different species. Latham appears to have
had three specimens, which were all three different from each other. Both
Forster and Ellis, in their unpublished drawings in the British Museum, as
well as Latham, evidently considered all three to belong to the same
species, and it is not advisable now to over-rule their verdict, given with
the specimens before them, merely on account of the different plumages,
since we all know that most waders, and especially brightly-coloured ones,
differ considerably in plumage, according to age and seasons. We are
convinced that "_P. ellisi_" has been a younger bird. Sharpe attaches
importance to the different habitat, but this is no argument in this
instance, because Eimeo is, at the nearest point, not more than seven and a
half miles from Tahiti,[2] and it is quite against all precedents among
_Charadriidae_ and beyond all plausibility that two such closely situated
islands have closely allied forms of a Wader.
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