Southcott's* Lichen Family
Crust-like or leafy or shrubby tufts usually colored grey, yellow, or greenish yellow. Found on stone walls, bricks, or trees. They live on the air, have a green colored line under the epidermis.
The Iceland Moss which is edible belongs to this family.
*Mary Southcott. Some Newfoundland Wild Flowers.
St. John's, Newfoundland : Robinson and Company , 1915, p. 37-38