292 PROF. W. K. PARKER ON ^GITHOGNATHOUS BIRDS. 



whole matter very bewitching, suggesting that we are somewhat near the stock (phylum) 

 from which the multitudinous Passerines have sprung. 



Moreover every patient fellow worker will see eye to eye with me, that in the south 

 we find the most struthious types, and in the north the highest, and that our bird- 

 groups are as important for study in their geographical distribution as in their taxonomy 

 or their morphology. 



The " Trochilidae " and " Caprimulgidse " have to be treated of separately ; and the 

 " Celeomorphge " (Woodpeckers and Wrynecks, classed togetlier) may be designated, 

 facially, as the " Saurognathse." These latter are peculiarly lacertian in their face ; the 

 Humming-birds and Goatsuckers are schizognathous, not segithognathous, as Professor 

 Huxley supposed {op. cit. p. 454). 



I find upon close examination that the " J^githognathse " admit of three morpho- 

 logical subdivisions, and the " Desmognathse " of four ; and as the remainder of this 

 research may have to rest awhile, these subdivisions may be given here. 



The " ^githognathae " present the three following modifications in their structure : — 

 a, incomplete ; b, complete ; c, compound. 



a. Incomplete. — .lEgithognathism occurs in the " Turnicomorphse" {Ilemipodius, 

 Turnix). Here the vomerine cartilages (cartilages to which the symmetrical vomers are 

 attached)' are very large, and incompletely ossified, and the broad double vomer has a 

 " septo-maxillary " at each angle ; but these bones are only strongly tied to the " ali- 

 nasal " cartilage, and do not graft themselves upon it : their union is with the vomerine 

 cartilage. 



b. Complete : Var. 1. — This occm-s in some of the lowest harsh-voiced " Coraco- 

 morphse." The vomers are developed in large vomerine cartilages, which they often 

 only partially ossify ; but these osseous tracts are distinct from those of the often bony 

 alinasal walls and turbinals. A small " septo-maxillary," one each side, generally appears 

 limpet-like, on the inturned angle of the alinasal cartilage, but does not run into it ; 

 this is well seen in Fachyrhainphus, Piiyra, and Thamnophilus. 



Var. 2. — This occurs in an immense group comprising the higher " Coracomorphse " 

 and also the Swifts (Cypselidse). Here all the vomerine bones are grafted upon the 

 nasal wall, and thus the bird loses its primary " schizognathism." 



c. Compound. — This form of face occurs when, superadded to the perfectly segitho- 

 gnathous face, desmognalhism is produced by ankylosis of the inner edge of the maxil- 

 laries, with a highly ossified " alinasal " wall and nasalseptum. Examples Gymnorhina 

 tibicen, Paradisea fapuana, Artamus leucorhimis. Of this type a feebler form is 

 produced when the maxillaries only coalesce with the ossified alinasal wall, as in Dendro- 

 colaptes albicollis, Thamnophilus doliatus, and Phytotoma rara. 



It may be as well to mention here the varieties of the " desmognathous " palate. 



' These belong to the labial category, and can be identified with similar elements in the face of the Snake, 

 Frog, and Shark. 



