FIGURE 4. Visual inspection of facets. 1. all facets present, number of facets is 4 (BMNH-M.19429, S. hundsheimensis); 2. facet 7 absent, number of facets is 3 (BMNH-M.1948, S. hundsheimensis); 3. no facets present, number of facets 0 (BMNH-25.5.23.1, C. simum).