Jl. Dhondt et M. Goyffon, OBSERVATIONS ON THE ELECTROPHORETIC POLYM ORPHISM OF SPIRORBIS-SPIRORBIS (ANNELIDA, POLYCHAETA), Bulletin de la Societe zoologique de France, 119(4), 1994, pp. 365-371
Spirorbis spirorbis (Linne), an annelid with larva able to metamorphos
e some hours after its release, presents, as various bryozoans species
having similar larval biology, a clinal variability from Brittany to
the Arctic polar circle.