THE MIDDLE EAR 689 



a flaccid appearance in comparison with the tense condition of its other 

 parts. This portion is known as the membrana flaccida or Slirapnell's 

 membrane. 



THE AUDITORY OSSICLES 



These are three in number, the malleus, the incus, and the stapes ; 

 they form a continuous bony chain, extending from the insertion of 

 the manubrium mallei in the tympanic membrane to the fenestra vestib- 



FIG. 575. THE AUDITORY OSSICLES. 



I, ossicular chain of the left ear; 1, malleus; 2, incus; 3, stapes. II, ossicular 

 chain of the right ear; 1, malleus; 2, processus gracilis; 3, manubrium; 4, long process 

 of the incus; 5, short process of the incus; 6, stapes. (After Riidinger.) 



uli, with whose margin the foot of the stapes articulates. The ossicles 

 consist of compact bony tissue containing loosely packed Haversian sys- 

 tems; they are united with each other by firm fibrocartilaginous ar- 

 ticulations. With the exception of the stapes, none of the ossicles contain 

 a marrow cavity. 



The manubrium of the malleus is firmly fixed in the tympanic mem- 

 brane, as already described, the head of the bone articulating with 

 the head of the incus in the epitympanic recess. The long process of 

 the incus, circular in transection, extends downward along the tympanic 

 wall in a course nearly parallel to that of tbe manubrium mallei, being, 

 in a portion of its course, contained within a recess in the osseous wall 

 of the tympanum. Finally, at the level of the stapes it makes a sharp 

 bend, almost at right angles with its former course, to articulate, by 

 means of a rounded end or orbicular process, with the head of the 



