| class | small class of marine mollusks comprising the chitons |
|---|---|
| class | whisk ferns |
| class | whisk ferns |
| class | extinct gymnosperms most of Carboniferous to Jurassic: seed ferns and allies |
| class | class of fungi in which the fruiting body is a perithecium |
| class | class of cold-blooded air-breathing vertebrates with completely ossified skeleton and a body usually covered with scales or horny plates |
| class | coextensive with the Rhodophyta: red algae |
| class | characterized by the formation of pseudopods for locomotion and taking food: Actinopoda |
| class | small class of bilaterally symmetrical marine forms comprising the tooth shells |
| class | a former classification |
| class | coelenterates in which the polyp stage is absent or at least inconspicuous: jellyfishes |
| class | horsetails and related forms |