from The Century Dictionary and Cyclopedia
- In Lamarck's classification, 1801, one of two divisions of his conchiferous Acephalæa, containing the equivalve bivalves: opposed to Inæquivalvia.
- In Latreille's classification, 1825, one of two divisions of pedunculate Brachiopoda (the other being Inæquivalvia), represented by the genus Lingula. See cut under Lingulidæ.
Sorry, no etymologies found.