Figure 9. A in Calcareous sponges of the genera Clathrina and Guancha (Calcinea, Calcarea, Porifera) of Norway (north-east Atlantic) with the description of five new species

Figure 9. A, Clathrina nanseni at 5 m depth. Scale bar = 1 cm. B, habitus of a fixed specimen. Scale bar = 1 cm. C, spicules of C. nanseni. tr = regular triactine. te = regular tetractine. Scale bar = 100 µm. D, tetractine with rudimentary and rounded apical actine. Scale bar = 100 µm. E, sharply pointed apical actine of a normal tetractine (ap). Scale bar = 100 µm. F, section of ascon tubes with the apical actines (ap) projecting into the interior of the tube. Scale bar = 100 µm.