Presumed female Bess Beetle, length about 35 mm. I like this photo because you can see several adaptations for the beetle's tunneling lifestyle--notes. I'll post some photos later of the unrelated Scarites, a ground beetle that burrows--it has a rather similar form.
I found a pair of these beetles under the bark of a rotting log. I tore the log up looking for the larvae, which I have never photographed, but had no luck. Having captured a pair, I'm going to try and rear them. (I felt a bit guilty about tearing up the log, too, disrupting their home--I normally do nothing more than pull off a bit of bark.)