AN ILLUSTRATED GUIDE TO THE BENTHIC FORAMINIFERA OF THE HEBRIDEAN SHELF, WEST OF SCOTLAND, WITH NOTES ON THEIR MODE OF LIFE

The Hebridean shelf presents a contrast in substrate type between higher energy open shelf sands, which are influenced by storm waves and lower energy muddy sands in depositional sinks called ‘deeps’. The latter reach outer shelf depths (>100 m) even when situated close to land (e.g., Muck Deep). The primary purpose of this paper is to illustrate the majority of the benthic foraminifera. For most species, information is provided on whether they are epifaunal or infaunal, based on their distribution in rose Bengal stained samples. Since the redox boundary is shallow in this area (less than 4-5 cm), infaunal taxa are most abundant in the top 1 cm of sediment and decrease in abundance down to 2 or 3 cm with no subsurface maxima as recorded elsewhere. Some dead tests are infilled with glauconite which preserves the form of the species even when the shell is lost. The organic-cemented agglutinated fauna was concen-trated by treating the samples with dilute acid to dissolve the calcareous forms. The species diversity of the resultant acid-treated assemblage (ATA) has been compared with that of the original dead assemblage (ODA). The pattern for the Hebridean shel