| Messoplana pacifica Karling, 1986 | Mar 1969 |  | gravel, stones, algae | gravel, stones, algae.  collected from the beach at the Laboratory. | 
| Ceratopera axi (Riedl, 1954) | Mar 1968 | intertidal | shell gravel |  | 
| Polycystis hamata Karling, 1986 | Sep 1960 | intertidal | algae | shell and algae in shallow water, tide pools | 
| Polycystis hamata Karling, 1986 | Mar 1969 | intertidal | algae | shell and algae in shallow water, tide pools | 
| Multipeniata (Multipeniata) californica Karling & Jondelius, 1995 | Mar 25, 1969 |  | gravel | small beach near Hopkins Marine Biological Station, under sea weed, low water. | 
| Plagiostomum hedgpethi Karling, 1962 | Sep 12-14, 1960 | shallow waters | sand | from seaweed, and in sand under wrackbeds, tide pools. | 
| Plagiostomum abboti Karling, 1962 | Sep 13, 1960 | tidepool | stones, gravel | washed off seaweed, tidepool. | 
| Archimonocelis semicircularis Karling, 1966 | Sep 13, 1960 |  | shell gravel, stones | tidepools close to the laboratory, washed out from shell gravel, stones and seaweed. | 
| Monocelis hopkinsi Karling, 1966 | Sep 11, 1960 |  |  | tidepools on the beach close to the laboratory. | 
| Minona cornupenis Karling, 1966 | Sep 11-14, 1960 |  |  | a small sandy beach at the entrance to the station area [Hopkins Marine Station], subsoil-water. | 
| Notoplana acticola (Boone, 1929) | Feb, 1953 |  |  | common under the rocks in shallow water adjacent to the laboratory. | 
| Cylindrostoma triangulum Karling, 1962 | Sep 14, 1960 |  |  | a small beach at the entrance to the Marine Station, with plankton net from algae in shallow water. | 
| Alcha evelinae Marcus, 1949 | Sep 1960 |  |  | tidepools. | 
| Groveia unicornis Karling, 1980 | Sep 13, 1960 |  |  | washed from sand and seaweed in a tidepool. | 
| Reinhardorhynchus  bispina (Karling, 1980) | Apr 7, 1969 |  |  | stones and shell gravel. | 
| Reinhardorhynchus  curvicirrus (Karling, 1980) | Apr 13, 1969 |  |  | shell gravel and holdfast of kelp. | 
| Paraschizorhynchoides glandulis hopkinsi Karling, 1989 | Mar 1969 |  | sand | clean sand at the high-water line. |