164 GENERAL ORNITHOLOGY. 



external lamina. It is well shown in a Passerine or Raptorial bird, wliere the postero-external 

 angle (between the outer border and the jiosterior end) of the palatal is well-marked, or may 

 be acutely produced ; there is no such lamina in a fowl, where the palatals are for the most 

 part slender aud rod-like. An internal, more or less vertically produced, plate to make the 

 mid-line rostral or vomerine connection is the superior internal lamina, or medio-palatine pro- 

 cess; very strong, for example, in a fowl, where it forms all the expanded part of the bone, and 

 . ends anteriorly as a sharp inter-palatine spur. The medio-palatine is probably to be regarded 

 as the main body of the bone, being the most axial part,, of the moslj extensive and varied con- 

 nections. A third lip or plate of the palatal is the inferior internal lamina, looking downward ; 

 it is generally very evident, but in a duck or fowl is reduced to a mere ridge, indicating where 

 the superior internal and external laminae meet. A duck's palatals are quite different in ap- 

 pearance from those of most birds, aU the posterior parts just distinguished being reduced and 

 constricted, while the fore ends, running abruptly into the hard-boned beak, are much expanded 

 horizontally (fig. 78). The postero-extemal angles of the palatal (formed by the external 

 lamina), even when much ju'oduced, may not reach as far back as opposite the pterygo-palatine 

 articulation ; or they may surpass these limits, and when they do, such backward prolongation 

 is called post-palatiue, the palate being considered to end at the pterygoids. In like manner, 

 the maxillary processes of the palatals, or the palatal strips as prolonged into the premaxillary 

 region, are called lyre-palatines. The inner posterior process, by which the palatine is articu- 

 lated with the pterygoid, is his pterygoid x)rocess. 



The Premaxillary Boues (figs. 62 ; 63, a; 69, 70, 71, 80, px; 75 to 79, pmx), also called 

 Intermaxillaries, form most of the upper beak, attaining enormous development in birds, and 

 reversing the usual relative size of premaxillary aud maxillary. Mainly determining as they 

 do the form of the upper mandible, their shapes are as various as the bills themselves of 

 birds ; but their generalized characters can be easily given. Each premaxillary, right and 

 left, forms its half the bill ) the two are always completely fused together in fi-out, commonly 

 presenting traces at least of their original distinction beliiud. They are commonly called one 

 bone, the premaxillary. Each is a triradiate or 3-pronged bone ; one upper prong, the most 

 distinct, called i\ie. nasal ov frontal process, forms with its fellow the culmen (p. 101, fig. 26, h) 

 of the bill. These processes, side by side, run clear up to the frontal bone in birds, driving the 

 nasal bones apart from each other. Such a median fronto-premaxiUary suture, with lateral 

 fronto-nasal aud uaso-premaxiUary sutures, is highly characteristic of birds, — an aiTangement 

 ])robably exceptionless. Two other hoiuzontal prongs on each side, extensively distinct from 

 the frontal process in most birds, but less separate fi'om each other, run horizontally along the 

 side and roof of the mouth for a variable distance. These horizontal prongs are an external or 

 dentary process (fig. 80, dpx), forming the tomium (p. 104) of the biU, and reaching back to 

 join the dentary part of the maxiUary ; and an internal or x>a^cital process (fig. 80, 2^P^)> run- 

 ning along the commencement of the bony palate. With this latter the anterior ends of the 

 palatal boues unite, — either on the side toward the mid-line of the beak, or between the palatal 

 and dentary processes, as in a woodpecker (fig. 80). Great laminar expansions inward of these 

 palatal parts of the premaxiUaries roof the hard part of the mouth anteriorly, though there is 

 usually a vacancy between the premaxillary hard palate and that formed farther back by the 

 maxillo -palatines and palatines. The posterior extremities at least of the frontal processes of 

 the premaxiUaries are commonly distinguishable from each other, as well as from the frontal 

 and nasal bones — in fact, these fronto-naso-premaxillary sutures are among the most per- 

 sistent of all. The divergence of the frontal fi-om the palatal and dentary processes bounds the 

 external nostril in part, the circumscription of that orifice being completed by the prongs of the 

 nasal bones. The superficies of the premaxillary bone, like that of the dentarv piece of the 

 lower jaw bone, is commonly sculptured with the impressions of the vessels and nerA'cs which 



