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MANUAL OF ZOOLOGY 



SECT. 



istic parts of the bird's skeleton. It is a broad plate of bone 

 produced ventrally, in the sagittal plane, into a deep keel or 

 carina sterni (car), formed, in the young bird, from a separate 

 centre of ossification. The posterior border of the sternum 

 presents two pairs of notches, covered, in the recent state, 



an 



FIG. 279. Columba livia. Skull of young specimen. A, dorsal; B, ventral; C, 

 left side. al. s, alisphenoid; an, angular; ar, articular; b 0, basi-occipital; 

 d. dentary; e. o, ex-occipital; eu, aperture of Eustachian tube;y". m, foramen 

 magnum; f-r, frontal; i. o. s, inter-orbital septum; ju, jugal; Ic, lachrymal; Ib. s, 

 lambdoidal suture; m. eth, mesethmoid; >_r, maxilla; mx. p, maxillo-palatine 

 process; na, no.', net" , nasal; o. c, occipital condyle; or.fr, orbital plate of 

 frontal; pa, parietal; pa. s, parasphenoid (rostrum); //, palatine; /. mx, pre- 

 maxilla; pt, pterygoid; qu, quadrate; s. an, supra-angular; s. a, supra-occipital; 

 sg, squamosal; ty. tympanic cavity; II. XII, foramina for cerebral nerves. 

 (From Parker's Zootomy.) 



