Fleemo wrote:

Well, I don't pretend to be a plant expert, but it *sure* looks like
Monarda to me,

Oh, it's Monarda allright, just not seedlings. Clear as mud? :-)

As I recall, my monarda wasn't clumplike at all, but grew in
individual stalks, flowered, then perished completely.

Semantics, methinks. The plant grows into large clumps, but the habit
is vertical (http://www.stauder.net/bildearkiv/Mo...0hybr%20RS.jpg).

The next year,
seedlings like the ones pictured appeared in its place, but never
flowered. It is a pretty shady area, but I thought I'd read that
Jacob Cline did alright in semi-shade.

The "seedlings" you're seeing are most likely "rootlings". IOW, they
are spreading from the root of the plants you had there previously. You
can trace the little leaves back to see this. I have no idea why these
are not flowering, but would suspect that they're not getting enough
sun. How tall did your plants get? Try moving them to a sunnier spot.

Suja