PEOF. W. K. PARKER ON ^.GITHOGNATHOrS BIRDS. 321 



between the septum and perpendicular ethmoid is very small above : it agrees, then, in 

 this respect, with Bendrocolaptes. 



The vomer (figs. 4 & 5, v) is very large, relatively ; and anteriorly it is twice as wide as 

 it is behind : this answers to Dendrocolajjfes. Here the vomers proper do not unite 

 with the inturned alinasal lamina (?'. a. I), but form the ossified and coalesced hinder 

 portion of the " vomerine cartilages " (v. c), which are longer, relatively, than in Turnix, 

 and reach more than halfway along the sides of the septum nasi towards the recurrent 

 lamina {re. c). 



This species and the Common Wren {Troglodytes vulgaris), where the two vomerine 

 cartilages coalesce in front, and the Hemipod, are the instances which satisfy me that 

 the vomerine cartilages are not merely the long extremities of the recurrent fold, 

 detached, and separately chondrified, through the rapidly produced " prognathism " of 

 the bird's face, but are a pair of upper labials. The broad shoulders of the vomer 

 are formed by the addition of a square septo-maxillary {s.moc) on each side ; and it is 

 this bone which grafts itself on the inturned alinasal wall {i. a. I). 



The pterygo-palatine arch is very similar to what I am about to describe in Synallaxis 

 and Muscisaxicola (PI. LIX. figs. 6 & 9). The pterygoid retains its distinctness (fig. 4, 

 pg) ; and its " hamular process " is long and slender. As in Muscisaxicola (fig. 9) and 

 Bendrocolaptes (fig. 1), the postpalatine ridges {ptpa) are fined ofl"; and as in Synal- 

 laxis (fig. 6), the slenderer transpalatine spurs {t.pa) are turned outwards as well as 

 backwards. Of the laminae that form the roof and the floor of the nasal passage, the 

 latter ends in a long interpalatine spur, and the former is arched (fig. 4, i.pa, e.pa). 

 The forward continuation of the palatines is very slender {pr.pa). 



The lateral ethmoids are large, square, and have one wide, large opening above the 

 antorbital, for the 1st and 5th nerves. The frontal region of the lateral ethmoid is 

 moderate, the os uncinatum below not distinct ; and there is no lacrymal, as far as I can 

 see ; the maxillo-palatines are not pedunculated (see fig. 4, mx.p, which shows the root 

 of this process). 



Example 12. Synallaxis flavigularis. 



Habitat. Chili. Section " Tracheophonae," Miiller ; family " Dendrocolaptidse." 



The skull of this bird is unrivalled for elegance and delicacy of structure ; this is 

 especially seen in the palate (PI. LIX. fig. 6). The swollen, cellular basitemporal plate 

 {b.t) is bat-shaped, and has the median part not much produ,ceid forwards. The para- 

 sphenoidal beam {pa.s) is very broad-based, and is without basipterygoid processes. 



From the Eustachian opening {eu) to the solid part of the prsemaxillaries, the basi- 

 facial axis is one continuous structure ; but the posterior or upper third of the trabe- 

 cular bar is separated from the ethmo-prsesphenoidal bar by a very large interorbital 

 fenestra ; the rest of this coalesced arch is in a state of permanent fusion with the 

 descending septal crest of the nasal organs. 



VOL. IX. — PART V. Becemher, 1875. 2 x 



