FIGURE 6. Grantia arctica. A–B in On some Calcaronea (Porifera: Calcarea) from the Barents Sea and adjacent Polar Basin

FIGURE 6. Grantia arctica. A–B. Habitus of specimens KFU-LH-2/036 and ZISP 10187, respectively. C. Detail of the outer surface with incurrent canals visible at right intervals. D–E. Cross sections. Abbreviations: ic = cortical triactines arranged around the incurrent canal; dt = tufts of diactines in the distal end of choanocyte chambers; cs = cortex; ttr = tubar triactines within the walls of choanocyte chambers.