268 PROFESSOR W. K. PARKER ON THE 
Example 45. Skull of Icterus vulgaris. Family Icteride. Group Oscines. 
Habitat. South America. 
On the whole, this species agrees very closely with the last. In some things it differs ; 
and, perhaps, being a younger specimen than the one studied, it is less ossified in its 
nasal labyrinth, the floor of which (Plate XLIX. fig. 2, n. jf) does not show the bony 
centres seen in the last. The septum nasi (fig. 3, s. 7”, ¢7) is ossified ; it is largely alate ; 
and its recurrent process is floored by a tongue of bone proceeding from the pre- 
maxillary (p.m). 
The vomer (v) has a wide head, in the horns of which a large septo-maxillary is 
seen, just where it is grafted on the inturned lamina (s.me., i.a.l). The maxillo-pala- 
tines (ma.p) are not knives, but pouches; they have a narrow pedicle, which has a 
pneumatic opening in it where it enlarges and bends; a larger mouth is seen outside 
the inflated end. 
This, as compared with the last, shows how variable a thing the pneumaticity of the 
bones is, and that there must be considerable variation in the distribution of the 
lesser air-cells. 
Example 46. Skull of Stwrnella militaris. Family Icterid. Group Oscines. 
Habitat. Chili. 
My picture-gallery will be greatly enriched by a lateral view of the face of this 
species, illustrating, as it does, the peculiarities of this type. 
The boss on the face-top (Plate XLIX. fig. 4, 1.pa), is seen dipping backwards to the 
skull, and descending steeply to the beak-point. Laterally, the nasal, lacrymal, and lateral 
ethmoidal mass (n, J, e.eth, p.p) ave all seen to come flush with the face. Above, the 
lacrymal forms a spongy subtriangular wedge jammed in between the descending crus 
of the nasal and the ecto-ethmoid. Halfway down it becomes a narrow rod, suddenly 
bent inwards; it forms an arch, turning outwards below, and spreading its base over 
the elegant egg-like os uncinatum (0.w), which almost reaches the zygoma (j). The 
vomer (fig. 4, v, sma, and fig. 4a, from above) corresponds very closely with that 
of the last, but has a median process in its front emargination. The thick ossified 
septum nasi (s.”) has three converging ridges, a fenestra in front, and a very large 
notch below it and the mesethmoid. The ale and the alinasal and inferior turbinals 
are soft. 
At the obtuse lateral facial angle the upper jaw is lifted at the side, like a dog’s 
lips in snarling, to make room for the crested mandible; here the more median struc- 
tures are seen, viz. the palatine, with its deep rib-edged transpalatine process, and the 
palato-maxillary bone nearer the outer margin (fig. 4, t.pa, p.ma). The pterygoids 
and mesopterygoids are like what I have described in the first species: here, however, 
these parts are nearly ankylosed. 
