270 PEOFESSOR "W. K. PAEKER ON THE 



spike (fig. 6, t.pa) being scarcely more developed than in the lower forms of the 

 Coracomorphae. The interpalatine spurs are large, and the ethmo-palatines about 

 equal («.^ff, e.pa). The palato-maxillaries {p.mx) are much more acerose ; and the 

 maxillo-palatines are large pneumatic " ladles," with an inferior gaping aperture. 



The vomer has a notch in front ; and, above, it runs as a bony " horn " into the in- 

 turned lamina {i. al) ; it sends down a sharp ridge from each outer edge. In E. mili- 

 nria the rostrum is very naked or scooped below ; in E. citrinella it is much less so. 

 In this latter species the tympanic bullse are extremely large and very elegant. 



Example 49. Skull of the Snow-Bunting [Plectrophanes nivalis). Family Emberizidse. 



Group Oscines. 



Habitat. Great Britain. 



In this species the concavity of the rostrum, below, is reduced to two submedian, 

 widish, shallow channels, divided by a ridge which ends in a median spur (Plate XLIX. 

 fig. 7). This spur is seen in the other species (figs. 5 & 6), and it forms an exact 

 floor to the " recurrent lamina." 



The palatine, on the whole, differs but little from that of E. citrinella ; but it diverges 

 more to the transpalatine spike, and is not so steep. The lower lamina of the isthmus 

 is narrower, and runs into larger interpalatines ; the ethmo- palatine coils are thin and 

 dentate (fig. 7, i.pa, e.pa). The prsepalatal bars converge more, and are broader and 

 more lathy; they carry a palato-maxillary, which is intermediate in size between that 

 of the last two instances ; it is attached by a sort of " callus " of bone, by most of its 

 anterior half (the point is free), to the prsepalatine bar. The maxillary {nw) has an 

 unusual breadth in front of its jugal process; and its maxillo-palatine process {mx.p) 

 is flatter than in E. citrinella, broader than in E. miliaria, and is scarcely pneumatic. 



The vomer («) is almost oblong ; its sides descend as a steep ridge, as in E. citrinella ; 

 its under face is gently convex, answering to the gently concave upperside ; its crura 

 are broad, and their interspace scarcely twice as long as the notch in front. 



Where the septo-maxillary should appear (most probably it has been ankylosed), 

 there is, on the side of each thick vomerine cornu, a large pneumatic opening. 

 Just the " foot " of the inturned alinasal lamina [i. al) has received bony matter. The 

 chink for the first and nasal nerves is continuous on the left side ; but on the right 

 a lobe from the pars plana has converted it into two separate foramina. 



Example 50. Skull of Phrygilus fruticeti. Family EmberizidEe. Group Oscines. 



Habitat. Chili. 



I have provisionally placed this type amongst the Emberizidse ; it is equally 

 distinct from the typical Finches, is not a member of the Cardinal family, and does not 

 difl'er more from Plectrophanes nivalis than that species does from Emberiza miliaria. 



