Teloschistes flavicans. This species really is extremely sensitive to air pollution, and its distribution has shrunk to the south-west of Britain. It is never fertile, being sorediate. It occurs on trees with a basic bark, often high up, as well as on clirffs close to the sea. In the Scilly Isles, it can be frequent on short turf amongst rock outcrops. This photograph wa staken on cliffs at Jerbourg in Guernsey less than a mile from the T. chrysophthalmus. It is a protected species by law, and should never be collected. In the USA it is very rare while T. chrysophthalmus is scattered throughout the south.