A microscopic examination was made of the vertical distribution and abundance of particulate matter in six dissimilar cores of marine sediment. Two of the cores were taken in the intertidal and two in the shallow subtidal at stations in the vicinity of Woods Hole, Massachusetts. One core was taken in the Hudson Canyon and another at abyssal depths. Biological stains were used to identify potential food particles at the sediment-water interface, at two cm below the interface and at five cm intervals to a maximum depth of 20 cm.