PROF. W. K. PARKER ON GITHOGNATHOUS BIRDS. dll 
This skull, at first sight, might be taken for that of a Tanager; but it is widely dif- 
ferent: it corresponds in all essentials with that of Pipra. Notwithstanding the great 
expansion of the face in front, the palatine region is less divergent behind, and in some 
respects we get here a truer repetition of twrnicine characters than in Pipra. 
The bat-shaped basitemporal region has a broader middle part (Pl. LVII. fig. 4, .¢); 
the basifacial bar (pa.s) has no basipterygoids. ‘The hinge is not quite perfect; a bony 
isthmus connects the ossified septum nasi and perpendicular ethmoid above. 
There is no fenestra in the deep, stout, thoroughly ossified nasal septum separating 
the nasal from the trabecular portion (s., #7); and thus this type is, in this respect, 
intermediate between the Tinamou and Syrrhaptes (“ Gallinaceous Birds,” pl. xxxvi. 
figs. 1 & 4; and “ Ostrich Skull,” pl. xv. fig. 8, s., c.f. ¢). The triangular expansion at 
the fore part of the base of the septum is due to the coalescence with it of the “ recur- 
rent lamina.” The depth of the septum brings it into immediate contact with that 
retral process ; and the nose is not perforated as in Pipra, with its alate, shallow septum 
(fig. 3). 
The yomer (figs. 4 & 5, v) keeps its breadth better than in Pipra ; its less convergent 
crura are ankylosed to the ethmo-palatine spurs. As in Pipra (see fig. 2), the ox-faced 
yomer has only utilized the clavate hinder part of the “‘ vomerine cartilages” (v. c), which 
converge towards the septum, and are separated from the inturned lamine (é.a. /) by 
a very moderate distance (fig. 4). The alinasal wall with its turbinal is ossified 
throughout by endostosis. It is not so hard as the vomer; but these two bones keep 
their own proper morphological territory; and the line of junction of the two is at 
the roof of a deep rounded sulcus (fig. 5, 7. a. 7, v), covered by the curling inwards and 
downwards of the inturned angle of the alinasal. Exactly where the two osseous tracts 
meet at their inner side, a small limpet-like bony centre stands, looking forwards, and 
forming a boundary-stone between the alinasal and vomerine regions: this is the septo- 
maxillary (s.mx). It does not, as in the higher Coracomorphe, form an ectosteal patch 
to the alinasal wall, which has ossified independently of it. ‘The shoulders of the broad, 
stout vomer are strongly thickened and downbent to articulate with the maxillo-pala- 
tine plate (ma.p), the whole build of the palate being stronger than that of Pipra. 
Thus the inferior face of the vomer is excavated in front, and its fore edge has a squared 
emargination. Another upper palatal element, the os uncinatum, or “ palato-trabecular 
conjugational bone,” is here beautifully distinct (figs. 4,6, 7, 0.w), but has been dis- 
placed outwardly by the corvine lacrymal (/) from its earlier ecto-ethmoidal relationship 
(p.p, ¢.eth). This small seed-like bone has a rounded outer edge, and articulates by an 
inner suture with the lower and outer edge of the lacrymal; its mother substance was 
a secondary bud, growing from the outer edge of the trabecula. In this type the 
great lateral ethmoids, although less swollen than in Hemipodius, have a greater lateral 
development ; indeed they carry this to a greater extent than any known bird (figs. 4, 
6,7). The very narrow frontals covering the great outspread ethmoids (“ prefrontals ”) 
