Apparently there is in fact a 15th cat (or a 14th for you purists out there). If cataloged, it would have been Unknown #3, an as-of-yet unnamed cat that comes to my porch to eat the food my wife puts out. I wasn't able to get a picture, and I'm not sure I recall ever seeing it (they all look the same to me anyway). A shame really, rumor has it that it's missing a paw, I could have had some fun with that.
Interestingly, I received quite a few comments on these articles, almost all of which could be described as schadenfreude. There were also a number of questions, I will attempt to answer those in another post.