PEOr. W. K. PARKER ON .EGITHOGNATHOUS BIRDS. 305 



The trabecular arch, hidden behind by its under-beam the parasphenoid {pa.s), has no 

 basipterygoid processes. Beyond the " hinge " it is soft, and, as in the Cj ow, is first 

 narrow, and then spreads out as two oblique wings with a crenate and wavy margin [tr). 

 The pra-nasal cartilage has been absorbed ; and, beneath, the coalesced trabecular horns 

 have grown into a triangular tongue of cartilage : this is the " recurrent lamina " {re. c). 

 The ox-faced vomer {v) has two crescentic emarginations in front ; it is not uncommon 

 to find a fore-looking projection at the mid line. This bone becomes pinched behuid, 

 its sharp legs converging ; it has below a scabrous appearance from the loss of its peri- 

 osteum, which was supplying it with new osteoblasts. On its shoulders it carries the 

 great nasal vestibule ; its moieties are grafted upon the " inturned alinasal laminee " (/. 

 a. I). Neither in the young Eedstart, nor in the adult Whitethroat {Sylvia cinerea) have 

 I been able to detect any lateral ossicles or septo-maxillaries. I have also searched for 

 them in vain in the Wagtails {Budytes rayi and MotacUla yarrelli) ; but in the Willow- 

 wren {Phylloscoims trocMlus) they are very evident on each side 'in the substance of the 

 nasal cartilage. This bird differs in some other respects, as we shall see. In the Red- 

 breast {Erithacus macula) they are very small. The segmentation of the trabecular to 

 form the cranio-facial hinge is, if the now absorbed prsenasal be taken into the measure- 

 ment, in the middle of the bar. 



On each side of the septum nasi the nasal wall bends in as a wavy-edged floor-plate {n.f), 

 above which is seen the large alinasal turbinal {a. th). The coalesced priemaxillse are 

 such as we see in the young of all these birds, the dentary portion {d.}jx) largely over- 

 overlapping the maxillaries {mx), and the palatine spur {j).px) binding the outside of 

 the prsepalatal bar {^v-pa). 



The large vomer almost wedges aside the moieties of the palato-pterygoid arch as 

 much as in the " Ratitse." Indeed the adults of the Coracomorphse seldom form any 

 thing like a " palatine commissure " such as is so common in other perching and climb- 

 ing birds. The right and left bars are bound together by the inwedged vomers ; and the 

 practical commissure is made by the early fusion of these bones. 



The long, slender, rounded pterygoids — more slender still in the adult — have but a 

 little epipterygoidean process in the young {e.-pg) ; but this is evident and well formed in 

 the old bird. A '■ mesopterygoid " {ms.^ifj) is breaking itself off from the fore part, 

 where it overlaps the palatine. But for the diagnostic transpalatine lobe of cartilage 

 {t.pa), the body of the palatine would be the almost exact counterpart of that of the 

 Hemipod (see PL LIV. fig. 1, pa), the main difference being the greater lengtli of the 

 ethmo-palatal spurs that bind the outer edge of the vomerine crura. The transpalatine 

 element answers very exactly to that of the Crow, being a rounded auricle ; but in the 

 adult (at least in Sylvia cinerea) the periosteal layers grow backwards, and give it an 

 angular finish behind. The maxillary (fig. 13, mx) ends in front as far forwards as 

 the palatine, and behind almost reaches the quadratum. The delicate jugal {j) nearly 

 reaches the angle of the praemaxillary in front. The maxillo-palatine process {mx.p) is 



VOL. IX. — PART V. December, 1875. 2 T 



