Thallus foliose to subfruticose, brownish gray to brown, the margins with long cilia which also at intervals attach the thallus loosely to the substratum; mainly dichotomously branched, the lobes narrow, 0.2-1.5 mm broad, dorsiventral; the upper side rounded and with very fine pubescence, the edges rolled over to make the underside canaliculate; the lower cortex lacking on underside and white loose hy-phae showing. Lobes 200-300 µ thick; upper cortex 30-120 µ thick, algal layer not continuous, medulla 140-180 µ. Apothecia toward the tips, more or less stalked, 1—4 mm broad; disk dark brown, sometimes white pruinose; margins entire, the back spinulose; hymenium 150-170 µ, hyaline, spores 8, brown, 1-septate, the walls of uniform thickness, thin, 30-42 X 12-18 µ.

Reactions: K — , C — , KC — , P — .

Contents: No lichen substances demonstrated.

This species grows on barks (Picea and Thuja) and commonly on rocks. It appears to be a circumpolar boreal species which is not commonly collected. The similar Anaptychia ciliaris (L.) Korb. with which it has been confused has broader lobes, more than 2 mm broad, and lacks the spinules on the apothecia. A. kaspica in North America ranges from Alaska east to Labrador and Newfoundland, south to Minnesota, Michigan, and New England. This is the only species of Anaptychia to reach the Arctic. Although present in Iceland and in North America it has apparently not yet been collected in Greenland.