As mentioned in an earlier article1 on the structure of the stapes, more precise information has been needed on the development and the adult form of this ossicle; until such information was made available, pathologic structure of the stapes could not, with certainty, be distinguished from normal. Equally important is information concerning the histologic nature of the vestibular window, the nearby fissular tracts through the otic capsule and the islands of chondral tissue situated in or near the latter. The current paper represents a second phase of this study and includes the description of six stages from the fetus at term to the adult of 70 years. A third article will trace the developmental changes which occur between midfetal life and term. Curiously, while structures in the general locality of the stapes have been described fully in recent publications, the ossicle itself has received little attention. Thus, the fissula ante