169 
THE ANATOMY OF BIRDS. — OSTEOLOGY. 
EEN 
Fic. 75. — Dromceognathous skull of ostrich, 7-8 nat. size, from specimen No. 16,629, U. S. Nat. Museum, by Dr. R. W. Shufeldt, U.S. A. &&, rostrum, beyond 
which the ossified nasal septum continues in the axis of the skull to the letters ‘“‘ Pmx.” V, the short vomer, borne upon /, uniting laterally with Map, the broad 
maxillo-palatines; P/, palatines, remote from rostrum, underrunning beyond Mxp, but not to Pmx. Pt, expanded scroll-like pterygoids, articulating behind with 
Btp, the strong basipterygoid processes on the body (not rostrum) of the sphenoid; they underlap 2, but do not articulate there. Pm, premaxillaries ; Mv, maxil- 
laries, whose ends run forward to opposite the letters ‘‘ Pmx”’; j, jugal; qj, quadrato-jugal; Qu, quadrate. (N. B. This is the most exceptional case of dromzeogna- 
thism. Each one of the Ratite families, — Struthionide, Rheide, Casuariide, Dinornithide, and Apterygide ,—as well as the Carinate family Tinamida, offers 
a special case of such formation, as explained in the text.) 
articulate with facets which are situated 
p] 
body of the basisphenoid and not from the rostrum 
This is 
” 
nearer the posterior than the anterior euds of the inner edges of the pterygoid bones.’ 
