Published online by Cambridge University Press: 11 May 2009
INTRODUCTION
Venus striatula (da Costa) (= Venus gallina L.) occurs in high densities in shallow water on a bottom of clean fine sand in the Bay of Douarnenez. The environmental conditions are characterized by an obvious sediment instability due to a high exposure to westerly swells (Guillou & Le Moal, 1978). This species is preferentially distributed in the fine sands (Petersen, 1913; Thorson, 1957), but is relatively tolerant towards certain ecological factors and so is sometimes found in very muddy sediments. It also shows an extended latitudinal range, since it is recorded from the Lofoten Islands to the Canaries, in the Mediterranean and the Black Sea (Tebble, 1966).