| Species | Name Used |
|---|---|
| Siphonosoma novaepommeraniae Cutler, E.B. | Siphonosoma novaepommeraniae (p. 139 ) |
| Sipunculus mundanus Selenka & Bülow, 1883 | Xenosiphon mundanus (p. 138 ) |
| Sipunculus natans Cutler, E.B. | Sipunculus natans (p. 137 ) |
| Sipunculus norvegicus Danielssen, 1869 | Sipunculus norvegicus (p. 137 ) |
| Sipunculus robustus Keferstein, 1865 | Sipunculus robustus (p. 137 ) |
| Sipunculus titubans Cutler, E.B. | Sipunculus titubans (p. 137 ) |
| Themiste huttoni Cutler, E.B. | Themiste huttoni (p. 146 ) |
| Themiste lageniformis Baird, 1868 | Themiste lageniformis (p. 147 ) |
| Themiste minor (Ikeda, 1904) | Themiste minor (p. 147 ) |