6
Inflated foliose thalli of
Hypogymnia
Crustose lichens
: they develop in 2 dimensions just as foliose lichens, but the lower surface adheres
completely to the substrate.
In some crustose species, the thallus is clearly lobed (placodioid)
Squamulose lichens
: the thallus consists of small scales.
Squamulose primary thallus of
Cladonia
(see later).
