164 EDWARD L. RICE 
a similar blastemic character, so that a slightly tangential section 
passes, with no perceptible histologic change, from the stalk of 
the columella, through the footplate, into the capsular wall. 
It should also be carefully noted that the above contrast in the 
histological character of the footplate and the capsule does not 
apply to the whole of the capsule, but only to that portion im- 
mediately surrounding the footplate and destined to develop 
into the closing membrane of the fenestra vestibuli, the mem- 
brana ovalis. This is framed by procartilage identical in its 
development with that of the columella. In later embryos the 
contrast of footplate and surrounding membrane becomes ever 
more conspicuous, the increasing distinctness being due no more 
to the progressive differentiation of the cartilage of the colu- 
mella than to the progressive differentiation of the fibrous tissue 
of the membrane. ‘The development of the cartilage of the rim 
of the fenestra vestibuli and of the footplate of the columella 
proceeds pari passu; in every stage the two are histologically 
indistinguishable. This is of importance, in view of the empha- 
sis laid by Bender (’11, ’12) and Kunkel (12 b) upon the differing 
degree of chondrification of columella and capsule as evidence 
that the two have no genetic connection. In Eumeces there 
is no such difference. Moreover, this criterion impresses me 
as essentially unreliable, and leading, if generally applied, to 
impossible conclusions. Thus the lateral and medial walls of 
the otic capsule, being of very diverse rates of chondrification, 
must be independent of one another; again, not only the early 
formed footplate of the columella, but equally the late-formed 
filling cartilage of the upper end of the foramen endolymphaticum 
in Eumeces, and, presumably, that of the ‘holes,’ noted in various 
parts of the otic capsule by Kunkel himself as well as others 
and explained as due to retarded chondrification (p. 149), must 
be interpreted as independent elements. Certainly, the rate 
of chondrification as a test of genetic relationship must be used 
with the utmost caution, if at all. 
Versluys (98) and Fuchs (09) have suggested that the relation 
of the columella to the periosteum or perichondrium of the 
otic capsule may be used as a means for determining the origin 
