376 



SKELETON OF THE FOWL 



each other only by the thin interorbital septum; (4) the 

 lower jaw is connected with the squamosal by a movably 

 articulated bone, the quadrate, which probably corresponds 

 to either the incus or the malleus of the rabbit ; (5) there 

 is only a single auditory ossicle, the columella ; (6) there are 

 no teeth. 



The fowl's skull may be readily divided into cranial and 

 facial portions which are loosely connected together, and 

 capable of slight movement upon each other. The cranial 

 portion consists of the cranium proper, or brain-case, and the 

 auditory capsules : the facial part is formed by the jaws and 

 the olfactory capsules. 



QJ B Q J D 



Fig. 66. — Gallua bankiva. The skull from the right side. (a. m. m.) 



A, articular surface of the mandible. AT, anterior tympanic recess, lead- 

 ing to Eustachian tube. B, pterygoid. C, occipital condyle. D, palatine. 

 E, rostrum. F, mandibular foramen. PO, fenestra ovalis. FR, fenestra 

 rotunda. FZ, zygomatic process of frontal bone. G, supra-angular. 

 H, dentary. IS, inter-orbital septum. J, jugal. L, lacrymal. M, maxilla, 

 MP, maxillo-palatine process of maxilla. K", nasal. OF, optic foramen. 

 PM, premaxilla. PT, posterior tympanic recess, Q, cLuadrate. Q J", quad- 

 rato-jugal. SF, olfactory foramen. SZ, zygomatic process of squamosal, 

 TF, foramen for fiftli nerye. 



1. The cranial portion of the skuU is a somewhat conical 

 box of bone, the base of which forms the hinder end 

 of the skull, the apex being directed forwards. In 

 the young skull the outlines of the component bones 



