l8o ELEMENTS OF OBNITHOLOGT. 



To the cranium thus understood, the bony framework of the 

 face is anteriorly annexed. It consists at its most anterior 

 end of a solid cone of bone called tlie pr&maxilla — the apical 

 portion of the upper bony jaw — which is attached to the skull 

 behind by six long, more or less slender bars ; but not all these 

 are parts of the premaxilla. One of these is median and 

 superior ; one is median and inferior ; two are external and 

 lateral (one on each side of the skull), and two are inferior and 

 intermediate — one on each side of the median inferior bar. 

 These six bars form the framework of the face. 



Attached to the side of the cranium, just behind the orbit 

 and in front of the external opening of the bony ear, is a very 

 irregularly shaped moveable bone called the os quadratum. 



The conical apex of bone — which really consists of two bones 

 (.premaxillm) anchylosed and united in one — extends backwards 

 in three diverging branches : one superior and two lateral. 

 The superior branch constitutes the median and superior bar 

 of the six bars just enumerated as making up the framework of 

 the face. 



Each of the two lateral branches of the premaxilla forms a 

 common base whence one of the two external and lateral bars 

 and one of the two inferior and intermediate bars, above men- 

 tioned, both take origin and thence project backwards. 



Each external and lateral bar of the face is an extremely 

 slender one, which passes backwards, from the lateral branch 

 of the premaxilla of its own side, to abut against the os qua- 

 dratum. This very slender bar is made up of three pieces, 

 whereof the more anterior is called, the maxilla, the median 

 one the jugal, and the posterior the quadrato-jugal. This 

 external and lateral bar is sometimes called the zygoma. 



Each inferior and intermediate bar of the face is an elongated 

 but less narrow piece of bone — called the palatine — which passes 

 backwards and inwards from the lateral branch of the pre- 

 maxilla of its own side, to abut — almost always — against the 

 side of the root of the "rostrum." Prom the sides of the 

 rostrum, just behind its normal junction with the palatines 

 and from the palatines themselves, two other elongated bones 

 called pterygoids extend outwards and backwards to articulate 

 with the quadrate bones. They may, as in the Ostrich, pro- 

 ceed outwards, not from the side of the rostrum, but from a 

 more posteriorly situated part of the base of the skull. Thus 

 each quadrate bone is embraced between the end of a pterygoid 



