Light (A, C) and scanning electron (B, D-I) micrographs of Difflugia elegans. (A, B) View of many specimens to illustrate variability in shape and size of the shell. (C-E) Lateral view of three specimens. (F) View of specimen with clogged aperture. (G) Apertural view. (H) Lateral view of apertural region. (I) Detail of organic cement network.