120 MR. W. K. PARKER ON THE STRUCTURE 



pier (quadrate) and proximal part of the mandible is much like that of the Swift. The 

 symphysis is long, and the distal part a mere copy of the upper jaw. 



The 2nd and 3rd postoral arches are merely outdrawn modifications of the normally 

 ornithic hyoid hone, much less specialized than in the Woodpeckers. The true cerato- 

 hyals (fig. 7, cliy) only extend for one fourth up the interior of the double horny sheath ; but 

 another fourth is filled, first with fibrous and then with fatty tissue. A short tract of 

 each bar is ossified, and all but the small bilobate end of the middle, or basi-urohyal bar 

 {bhy, bbr). The proximal part of the 3rd postoral (br) is only about one fourth the 

 length of the flat distal piece, which reaches, when the tongue is retracted, as far as to 

 the premaxillary apices : both are fully ossified. 



Any one who will repeat these observations will find that the " Trochilidae " have no 

 right within the Passerine territory, and that they have at length diverged very widely 

 from the most striking isomorphs within that range. The " Coccygomorphse," if they 

 be considered broadly, will be seen to be their truest relations ; they are not, however, a 

 normal branch, but should be looked upon as forming a very distinct secondary leader, 

 arising close to the root of this widely ramifying group. It is well worthy of remark that 

 that Caprimulgine outlier of the " iEgithognathae," the Swift, comes very much nearer 

 the Humming-bird than the " Nectariniidse," birds so mimetic and isomorphic of these 

 gorgeous " vertebrated insects." 



On the Structure of the Face in Scythrops novae-hollandise. 



It would be difficult to find a more central form than Scythrops for the whole of the 

 " Coccygomorphse." It appears to be equally allied to the Hornbills (" Buceridae"), 

 the Toucans (" Khamphastidae"), the Plantain-eaters (" Musophagidse "), and the true 

 Cuckoos (" Cuculidae"). This paper, however, is given, not so much for the elucidation 

 of a difficult taxonomy, as for the purpose of exhibiting the more striking modifications 

 of the face and nasal organs in highly specialized birds. Ankylosis is in this case carried 

 to its uttermost limits as far as is consistent with the well-being of the type ; yet the 

 regions can easily be determined. Rudiments of basipterygoid processes (Plate XXIII. 

 fig. 1, bpg) remain on each side of the subcarinate posterior part of the basifacial bar ; 

 the bar becomes rounded and synovial where it glides along the common palatine groove 

 (fig. 2, pe,pa). In front of the hinge the bony septum nasi becomes lost in the delicate 

 diploe that, sponge-like, fills the. large upper jaw. Besides the huge premaxillaries, 

 which have melted into the common mass of the upper face, there is a well-marked 

 vomer (figs. 1 & 2, v), which appears as a thickish subcarinate plate of bone between the 

 maxillo-palatine wedge and the approximated interpalatine lips. This lesser bony wedge 

 thickens again above, and then thins out to articulate by fibrous tissue with a supero- 

 posterior ossicle. The vomer of Scythrops is an azygous bone, of the Chelonian type, 

 such as is also seen in Raptorial Birds, and in Mammalia of the Cat tribe ; but the hinder 

 part has been detached, and has coalesced with the palatines (ptpa, v). 



There is, however, another element of the trabecular arch in this bird, which makes it 

 one of great interest to the morphologist ; this is the os uncinatum. Notwithstanding 

 the normally large size of the lacrymal (fig. 3, I), the ecto-ethmoid, or pars plana (pp), 



