Looking at my first picture a little closer... it looks like there is quite a bit of variation in my stool sample. Maybe slightly different critters? A couple small pieces seem to have the rounded edges like Daryl's specimen.
but hang on. i mean, ya'll may well be onto the right answer. but what's weird about the specimen in question, if those are coprolites, is the uniformity of them. they all seem almost exactly the same length and diameter, and the ends are rounded just so. the comparative material posted has much greater variance between individual poops.
Edited by toothpuller, 23 November 2009 - 08:59 PM.