_Columba rodericana_ Milne-Edwards, Ann. Sc. Nat. (5) XIX art. 3, p.
16, pl. 12, ff. 1, 1a, 1b, 1c (1874).
The original description of the sternum is as follows:--"It belongs to a
species small in size, barely as large as _T. tympanistria_, but evidently
much better built for flight. In fact the most striking characters of this
sternum are the large size of the bouclier, the large size of the lateral
notches, and the shape of the keel, whose anterior angle is not much
produced in front. The coracoidal grooves are large and only slightly
oblique. The lateral branches detach themselves from the bone in front of
the costal facets--they are very widely spread, and stretch more directly
outwards than in the remainder of the species of the family. The lower
lateral branches are equally divergent, and the median blade of the
posterior edge is remarkable from its enlargement. The keel is moderately
prominent, its anterior angle is much rounded, and does not reach the level
of the episternal apophysis, as is the case, as a rule, in the pigeons. All
these peculiarities, to which must be added the general flattening of the
bone which is hardly at all sloped like a roof, separate the pigeon of
Rodriguez very widely, not only from _Erythroena_ and _Turtur_, but also
from _Vinago_. In its shape in general, by the little pronounced keel and
the direction of the latter, this sternum presents certain analogies to the
essentially arboreal species such as those of the genus _Carpophaga_, but
they all differ in having the space for the costal facets on the sides of
the sternum much more extended, the superior lateral branches larger, and
the latter arising further back, so that the lateral notches are smaller.
Up to the present I do not know any genus of the family of _Columbidae_ in
which the sternum can at all be likened to that found recently in
Rodriguez, and therefore in all probability this fossil remainder is of yet
another vanished species, which I propose to call _Columba rodericana_."
(Translated.)
It is probable that Milne-Edwards's _C. rodericana_ belonged to the genus
_Alectroenas_, and was the representative on Rodriguez of the _Alectroenas
nitidissima_ of Mauritius. 1 humerus in the Tring Museum.
Habitat: Rodriguez.
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