ANIMAL MECHANISM. 



295 



bones, which we shall now endeavor to describe. The 

 tecimical phrase, ossicula auditus, in the Latin language, 

 implies little bones of the ear. They are by far the small- 

 est in the body. The first, in the order of their distribu- 

 tion is the malltus or mallet, having a faint resemblance 

 to that instrument, inasmuch as there is a long handle 

 joined to a round knob. Secondly, the inchus, from its 

 resemblance to an ovil : os orbicularc or round bone, 

 the least in size that has ever been discovered or probably 

 exists in any terrestial creature, being in man consider- 

 ably smaller than the smallest mustard seed. And lastly, 

 the stapes or stirrup, almost a miniature facsimile of a 

 saddle stirrup. Birds have but two of these, of which 

 the malleus is most developed. Turtles, of which I have 

 a specimen, have but one, the malleus ; and reptiles, as 

 far as personal dissection warrants, have but two. In 

 these classes, there is a departure in form, from those we 

 are contemplating in our own species. 

 Explanation of Fig. 6. FIG. 6. 



There are present- 

 ed here, a magnified 

 view of the ear bones. 

 The os orbicular e, or 

 round bone, is not 

 represented, being 

 considered by some 

 anatomists as only 

 an appendage of the 

 malleus. 



The malleus known 

 by its long arms : a, 

 b, c, d, e, mark the 

 same points as in 

 Figure 4. The in- 

 chus, resembling a 

 molar tooth, having 

 shorter arms, is in the same position as in Figure 4, the letters have 

 the same reference. The star points out the articulating surface 

 for the malleus. 



Any person, from the foregoing remarks, can recognise the stapes, 

 by its shape a 6 its head; c the neck; d anterior erus; e the 

 second; /the oasis. 



The fourth drawing represents another view of the stapes, seen 

 from above a its cartilage ; 6 anterior; c posterior; d the basis. 



