Accordin Algaebase, this name is currently regarded as a taxonomic synonym of Leathesia marina (Lyngbye) Decaisne

Commonly attached to other seaweeds and sometimes rocks. When young, the organism is solid but as it matures it become hollow and somewhat convoluted and has the appearance of a small leathery brown bag about the same size as a tennis ball. The texture is rubbery and the outer surface smooth.These brain-like brown seaweeds can be found growing on rock or as epiphytes on other seaweeds in the mid to low intertidal. Individuals can grow to ~15 cm in diameter. Young individuals can resemble other globular forms of algae. To determine if it is Leathesia, squeeze and flatten a piece between your fingers. Leathesia will break apart into filaments whereas other globular forms will flatten but remain intact.

Thallus forms distinctive yellowish-brown, hollow, globular cushions that are deeply convoluted. The individual fleshy thalli are 1-6 cm (0.4-2.4 in) across but may become larger as they grow into each other and form a bubbly carpet.

Original publication: Areschoug, J.E. (1847). Phycearum, quae in maribus Scandinaviae crescunt, enumeratio. Sectio prior Fucaceas continens. Nova Acta Regiae Societatis Scientiarum Upsaliensis 13: 223-382, pls I-IX.

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