Are they directional? I couldn't see a rotating direction when I put them on the bike the weekend. The tread pattern suggests they could be.

yeah they are, there is a direction on them somewhere

There's an arrow on the sidewall, but it should be obvious from the way the tread is ramped.

Here

thanks very much uplink.

If there's anything arrow-like in a tread, it should point forward on the front and backward on the back, when viewed from above.

If the blocks on the tread are ramped on one side, then if the ramps face forward when viewed from above this decreases the rolling resistance but reduces drive traction.

If the ramps face backwards when viewed from above this increases the rolling resistance and improves drive traction, but decreases braking traction.

tyre lables always go on the drive side.