Heat the oven to broil with the rack near the top. Clean the mussels, discarding any that are open. Bring the Pernod to a boil in a large pot, add the mussels, cover, and cook three minutes, or until opened. Drain and discard any mussels that have remained closed.
Mash the butter with the chives and tarragon. Put a pinch of the herbed butter on each mussel. Sprinkle over the breadcrumbs. Grind over some pepper. Broil until the crumbs are golden, about two minutes. Serve with lemon wedges for squeezing.