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A. G. POHLMAN 



duck) the tubal course of these hgaments is replaced largely 

 with involuntary muscle which becomes continuous with the 

 involuntary muscle at the common tubal orifice. Breschet pic- 

 tures the ligaments, but his account of the influence of traction 

 upon these ligaments or the indirect traction through the mus- 



CSL 



Fig. 11 Section through the length of the columellar-squamosal ligament 

 of an adult chicken; orcein stain. 



Fig. 12 Section through the quadrato-squaniosal articulation of an adult 

 chicken, showing the relation of the head of the quadrate (Q) to the fibers of the 

 columellar-squamosal ligament; resorcin stain. 



cles of the mandible attached to the tubal wall must be denied. 

 The bird does not possess the cartilaginous tuba auditiva of 

 the mammal. The function of the drum-tubal ligaments is 

 clearly one of limiting the amount of excursion in the extra- 

 stapedial, in particular the infrastapedial process, and will be 

 considered later. 



