Your guess is as good as mine (actually, if you know Princeton well, it's probably much better). Is this a horse's head? Is it a head of a sporting dog? Why is there a whole row of them? What's the other thing? Are they protected against the frost, or are they about to be unwrapped having traveled from somewhere else? I tried to pretend that they were a whole long line of outdoor chess pieces, but unless anyone's playing a strange game with 12 knights, that's probably not where they belong.