84 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
Galline Characters. — Pedate end of internal xiphoid process, arrange- 
ment of the costal facets, and shape of the distal end of coracoid. ; 
Cracine Characters. — Blunt, upright, subtriangular costal process, 
shallow inner sternal notch, small prepubis, proportions of pelvis, elon- 
gate tarsus with all the toes on the same level. 
Peculiar Characters. — Absence of recurved mandibular process ; 
short, stout, U-shaped furcula with large hypocleidium and articular 
facet for coracoid. 
The weight of the peculiar characters, particularly the absence of a 
post-angular process, are, as stated in the introductory remarks, sufficient 
to prevent the bird being placed in either the Cracide or Megapodide, 
thus necessitating the establishment of a new family, Gallinuloidide. 
The principal family characters are the absence of a postangular man- 
dibular process, presence of an articular facet on the furcula for the re- 
ception of the acrocoracoid, and the presence of an acrocoracvid. 
The generic characters are considered to be the stout U-shaped 
furcula, the shape of the scapula, and the anterior extent of the crista 
sternt, As specific characters are always comparative, none can be 
formulated from a single specimen, even did they not depend to so great 
an extent in birds — often entirely — on external features. 
This bird is interesting not because it presents any striking peculiari- 
ties of structure, but rather because it does not, and because it belongs, 
as we might naturally expect from its age, to a generalized type having 
points of structural resemblance with various families of gallinaceous 
birds. It is an additional reminder, were any needed, of the great gaps 
in our knowledge of the development of birds and of the rapidity with 
which they attained their present forms. The mammals of the Eocene 
are quite different from existing species, but this bird readily takes its 
place among the forms of to-day. 
