Sphaerophorus globosus (Huds.) Vain. forma
Thallus in small flattened cushion of 1-2 cm diam. and 0.5-1.5 cm height, formed by erected branches of 0.5-2 cm height, very dense and tightly packed one against the others, cylindrical section, ramified in a dichotomous way, branches and their ramifications very short with a digitate looking, show a diameter quite equal between each others and are ended with small cones of a lighter colour ; colour is grey-greenish in places slightly exposed to light, becoming brown-orangy like rust in more exposed places. Form not fertile in its stations. Medulla: C-, K-, CK+/- pink, Pd-, I+ blue a little pale lilac. Rare and unperceived, growing at the base of heath rocks very exposed to seaspray and marine winds in Islands and Capes in the tip of Brittany. N.B. This form reduced and a bit shrunk of Sphaeophorus globosus is very similar to Spherophorus fragilis, this latter being differentiated only by its I- reaction (often difficult to validate, as any negative reaction) ; it is probably this form which has been wrongly reported as Sphaeophorus fragilis in the Armorican massif by former lichenologists who collected plants there.*