| Archaphanostoma agile (Jensen, 1878) | | 5-10 m (0-40 m) | | |
| Avagina incola Leiper, 1902 | | | | common heart urchin, Echinocardium cordatum. |
| Convoluta convoluta (Abildgaard, 1806) | prior to 1905 | littoral | | |
| Cyrtomorpha saliens Graff L, 1882 | Jun, Jul prior to 1882 | | | |
| Convoluta flavibacillum Jensen, 1878 | prior to 1882 | | | |
| Microstomum groenlandicum Levinsen, 1879 | prior to 1882 | | | |
| Stenostomum leucops (Duges, 1828) | prior to 1882 | | | In mud of sediment of standing fresh water |
| Byrsophlebs graffi Jensen, 1878 | prior to 1882 | shallow | | Numerous in shallow depth between Fucus and Ulven. |
| Byrsophlebs intermedia Graff, 1882 | prior to 1882 | tide pool | | few specimens in a tide pool near Millport. |
| Proxenetes cochlear Graff, 1882 | prior to 1882 | tide pool | | one specimen in a tide pool near Millport. |
| Mesostoma robertsoni Graff, 1882 | prior to 1882 | | | |
| Pseudorhynchus bifidus Graff, 1882 | prior to 1882 | | | |
| Mesostoma rostratum (Müller, 1774) | prior to 1882 | | | |
| Macrorhynchus helgolandicus (Metschnikoff, 1865) | prior to 1882 | | | |
| Macrorhynchus croceus (Fabricius, 1826) | prior to 1882 | | | |
| Gyrator hermaphroditus Ehrenberg, 1835 | prior to 1882 | | | in a moor pool |
| Provortex balticus (Schultze, 1851) | prior to 1882 | | | |
| Provortex affinis (Jensen, 1878) | prior to 1882 | | | |
| Vortex viridis Shaw, 1791 | prior to 1882 | | | |
| Vortex schmidtii Graff L, 1882 | prior to 1882 | | | |
| Vortex truncatus (Abildgaard, 1789) | prior to 1882 | | | |
| Vortex millportianus Graff L, 1882 | prior to 1882 | | | |
| Plagiostomum vittatum (Frey & Leuckart, 1847) | prior to 1882 | | | |
| Plagiostomum ochroleucum Graff, 1882 | prior to 1882 | 3 m | | found in Laminarien in the harbor. |
| Vorticeros auriculatum (Müller, 1784) | prior to 1882 | | | |
| Allostoma pallidum Beneden, 1861 | prior to 1882 | | | tide pool |
| Cylindrostoma quadrioculatum (Leuckart, 1847) | prior to 1882 | | | hundreds in a tide pool of Little Cumbrae. |
| Monotus lineatus Müller, 1773 | prior to 1882 | | | |
| Monotus fusca (Ørsted, 1843) | prior to 1882 | | | |
| Aphanostoma diversicolor Ørsted, 1845 | 1882 or earlier | | | |
| Acmostomum dioicum Metschnikoff, 1865 | 1948 | | | uncommon. |
| Plagiostomum koreni Jensen, 1878 | Jul 7 and 19, 1948 | tide pool | Ascophyllum | north of the Biological Station |
| Plagiostomum vittatum (Frey & Leuckart, 1847) | Jul 2 and 19, 1948 | | | |
| Pseudmecynostomum flavescens (Dörjes, 1968) | prior 1975 | | | shore pool |
| Provortex affinis (Jensen, 1878) | 1913 or earlier | littoral | | |
| Maehrenthalia intermedia (Graff, 1882) | 1913 or earlier | | | |
| Astrotorhynchus bifidus regulatus Graff, 1905 | 1905 or earlier | | | |
| Promesostoma marmoratum (Schultze, 1851) | 1913 or earlier | | | very active, in marine and brackish water. |
| Promesostoma marmoratum marmoratum (Schultze, 1851) | 1913 or earlier | | | very active, in marine and brackish water. |
| Acrorhynchus caledonicus (Claperede, 1861) | 1913 or earlier | 1-3 m | | in ebb tide pools, and litoral zone in large numbers. |
| Polycystis naegelii Kölliker, 1845 | 1913 or earlier | | | living among plants in the litoral zone. |
| Polycystis crocea (Fabricius, 1826) | 1913 or earlier | | | |
| Phonorhynchus helgolandicus (Metschnikow, 1865) | 1913 or earlier | | | |
| Plagiostomum vittatum (Frey & Leuckart, 1847) | 1913 or earlier | | | |
| Vorticeros auriculatum (Müller, 1784) | 1913 or earlier | 0-35m | | littoral up to 35 m deep in Algen and Bryozoen. |
| Pseudostomum quadrioculatum (Leuckart, 1847) | 1913 or earlier | | | |
| Enterostomum coecum Graff, 1882 | 1882 or earlier | | | ebb tide pools. |
| Monocelis fusca Örsted, 1843 | 1913 or earlier | | | |
| Monocelis lineata (Müller, 1773) | 1913 or earlier | | | |
| Allostoma pallidum Beneden, 1861 | Jul 19, 1948 | tide pool | | tide pools on the shore, north of biology station. |
| Haplodiscus incola (Leiper, 1902) | 1905 or earlier | | | Firth of Clyde (Millport auf Cumbrae). Im Nebendarm von Echinocardium cordatum Penn |