170 



GENERAL ORNITHOLOGY. 



, PmJ!^ 



the gist of dromaognathism ; it is exhibited in several ways, (n) In Struthio alone, fig. 75, 

 the very short vomer, home upon the rostrum, articulates neither with palatines uor with ptery- 

 goids, but with the maxillo-palatines ; and the palatines, which are remote from the rostrum, 

 advance beyond the maxillo-palatines, as in must birds, (h) In Rhea, the vomer is as long as 

 usual in birds, and articulates behind with the palatines and pterygoids, but does nut join the 

 maxillo-palatines in front ; the short palatines uuite with tlie inner and posterior edges of the 

 thiu fenestrated maxillo-palatiucs. (c) In CasuariKs aud Drointriis (cassowary and emeu), 

 the long vomer articulates behind with the palatines and ]iterygoids, aud unites in fnmt with 

 the maxillo-palatines; these are flat, imperforate, and solidly joined to the premaxillte; the 

 palatines are short, (rf) The extinct Diiiornis had flat imperforate maxillo-palatine plates 

 uuiting solidly with the jiremaxilUe, and jirobably witli the vomer, as in Lromcriis. (e) In 

 Apteryx, the long vomer unites with palatines and pterygoids behiud : short broad palatines 



suture oliliquely with ilat imper- 

 forate maxillo-palatine plates, 



which uuite both with jiremax- 



illary aud vomer. (/) The tin- 



amous, Drominognathcc (flg. 76) 



■' liave a completely struthious 



palate " ; vomer very broad, Aixp 



uniting in fmnt with broad max- 



illo-palaliue jdatcs as in l)ro- 



mcciis; beliind articulating with 



posterior euds of palatines and pj. ^ 



anterior ends of pterygoids, both 



of which are thus prevented, as 



in all Ratitce, frnm any extensive 



connection with the rostrum ; 



basipterygoid processes springing 



from body of sphenoid, not from 



its rostrum, articulating with 



pterygoids very near the pos- 



terior'or outer ends of the latter ; ^'"- !'■ 7 ■''■'"--"P"""'""-' skull of 



cnniinon fnwl, luit. size. Irom ii.iture, 

 Fio. 76. — Dromirnpnntlious head of quadrate with a single by Dr K. W.SlmfeWt, U. S. A, Letters 

 skull of tiiiamoii {rmamus articuhir facet as in Rafihr. :is before ;/'«, iialatine. 



;'o?)*/.s"/)(.s) ; copietl by Sluifehlt * ) ^ 



from Hu.xley. Letters as be- 

 fore; M.rp, maxillo-palatine. gchizognathism (Gr. crxiCo, .^chi.-o, I cleave) is the kind of 

 "cleft palate" shown by the ccdunibiue aud gallinaceous birds, by the waders at large, and 

 many of the swimmers (see fig. 77)- In this general case, the vomer, whether large or small, 

 tapers to a point in front, while behiud it embraces the basisphenoidal rostrum, between the 

 palatines; these bones and the pterygidils are dire<'tly articulated with one another and with 

 the basisphenoidal rostrum, not being borne upon the divergent posterior ends of the vomer; 

 the maxillo-palatines, usually elongated and lamellar, pass inwards over \iiiidci; when" the 

 skuU is viewed upside-down, as it usually is] tlie anterior part of the palatines, with winch 

 they unite and then bend backwards, along the inner edge of the palatines, leavinn- a broader 

 or uan-ower fissure between themselves and the vonu'r, on each side, and do not unite witli ouo 

 auother or with the vomer. It ftdlows from this that in the dry skull of a plover, for instance 

 which shows the schizognathous arrangement extremely well, " the blade of a thin knife can 

 be passed, without meeting with any bony obstacde, from the posterior nares alongside the 

 vomer to the end (.if tlie beak." There are several groups of birds which exhibit the schizo- 

 gnathous plan, with ulterior modifications of pahital and other characters. (a) The colum- 



