298 Annals of the Carnegie Museum. 



face between this leaf-like area and the free-edge of the beak upon this 

 aspect is ornamented with a series of shallow pitlets, placed close 

 together upon either side, which have at their mesial terminations sub- 

 concealed foramina leading into the interior of the bone. Passing to 

 what may be called the horizontal portion of this upper mandible, we 

 find that its average width is somewhat less than the part we have just 

 been considering ; its narrowest portion being anterior to the narial 

 apertures. The culmen is flattened and very slightly rounded from 

 side to side, the nasal bones being large, broad and smooth. All 

 the sutures between these, the frontals, and the premaxillary are quite 

 obliterated in the skull of the adult, and the bill shows a tendency 

 to a slight rounded elevation, in front of the transverse, fairly-well 

 marked cranio-facial line. Either narial aperture is very large, sub- 

 elliptical in outline, and in no way separated from the opening of 

 the opposite side by an o.sseous nasal septum. In front of these aper- 

 tures, the sides of the superior mandible are lacking in a covering 

 of compact bony tissue, and as a consequence the cancellous nature 

 of the interior is considerably e.xposed at these places. This state 

 is continued backwards along the otherwise solid supero-median floor 

 of the nose, to a point where the large maxillo-palatines meet each 

 other across the middle line. The under surface of the upper beak 

 is upon the whole smooth, while its central longitudinal portion is 

 raised above the rest of the surface as a rounded crest or elevation. 

 This is best marked anteriorly, as it bifurcates and becomes flatter as 

 we pass to the rear posterior to the flexure, where it usually shows in 

 the median line a few foraminal elongated vacuities. These lead into 

 the cancellous interior of the bone. 



Regarding the superior aspect of the cranium proper we have to 

 notice that the frontal region is depressed, and triangular in outline ; 

 the base of this triangle being formed by the cranio-facial line, and 

 its apex by the approximation of the supra-orbital glandular depres- 

 sions. These last are very large and well marked in the Flamingo, 

 and closely approach each other in the median line. The trans-orbital 

 interval is narrow, and the supero-orbital peripheries are subcultrate, 

 or moderately rounded off. We are permitted to see also upon this 

 view of the cranium, the extensive suture, upon either side, formed 

 by the articulation of the lacrymal with the corresponding fronto-nasal 

 border. More posteriorly, the parietal region is rounded and smooth, 

 and is entirely lacking in anything like a median furrow extending 



