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off from the navicular than the preceding one — it is very much more 

 distinct than in any other that I have myself observed; more so, I 

 think, than in the remarkable case figured by Morestin. In my 

 examination of individual cuboids, I met one showing an articular 

 surface on the plantar side of the posterior process, but which was 

 not continuous with the articular facet on the proximal side of the 

 bone. 



It may be asked whether in view of the present observation, 

 which is an admirable illustration of Pfitzner's theory, I am inclined 

 to modify my criticism of that theory (2). I must say that I am not. 

 I pointed out then that as a working hypothesis it might be very 

 useful, but that it was neither complete nor quite accurate. In fact, my 

 studies of this element have confused me exceedingly. 



Pfitzner regretted that he did not give his attention to this 

 element until late in his researches. It is unfortunate that he should 

 not have been more precise in his definition of the various forms in 

 which it appears. It is important to note that in both of his two 

 main types which I mentioned at the beginning of this paper, in one 

 of which it is fused with the cuboid and in the other with the navi- 

 cular, he makes it articulate with the talus, which would seem to imply 

 that he looked upon this articulation as a characteristic feature of the 

 bone. In his account of the articulatio talo-cuboidea this seems to 

 be distinctly implied. In point of fact this articular surface on the 

 cuboides secundarium is almost always present when that bone is a 

 part of the navicular, the facet being, however, very rarely marked off 

 on the articular surface. Yet a typical projection on the cuboid (as 

 for instance that of the right foot of my specimen) is surely to be 

 considered as representing this element though the articular facet be 

 wanting. From a careful study of Pfitzner's writings I do not doubt 

 thai he was of this opinion. Apparently he would explain the want 

 of an articular surface for the talus by its having wandered from its 

 typical position. Pfitzner emphasizes the fact that its complete 

 absence has never been observed. There are many naviculars in which 

 it is so slightly indicated that no one would notice it but would assume 

 (if it must be somewhere) that it is on the cuboid. But yet there are 

 cases in which it is true of both the cuboid and the navicular that a 

 passing glance fails to find it on either, while a careful study finds 

 an indication of it on both. Hence Pfitzner must have meant that 

 it could be represented by the proximal plantar process of the cuboid. 

 This, indeed, is what one would expect from analogy, as it is the 



