- Dujardin, with some eighteen species.
- Dujardin, Ann.
- Passing over the earlier authors who regarded this group as allied to Infusoria, a view c ar first contested by Dujardin, T.
- Albertia Dujardin; Drilophagus Vejdovsky; Microcodon Ehr.
- Dujardin gave a less detailed but more accurate account under the name of Zoophytes Systolides.
- Dujardin, Histoire naturelle des zoophytes (1841); T.