Olson, O.P. 1956 The genus Baryspira (Mollusca) in New Zealand. Wellington: New Zealand Geological Survey. New Zealand Geological Survey paleontological bulletin 24. 32 p.
Abstract: The New Zealand species of the gastropod genus Baryspira (Olividae) are revised. Thirty-three species, three subspecies, and one variety are distinguished and figured. Three subgenera are proposed, twelve species, one subspecies, and one variety introduced, two species names become synonyms, and two become subspecies names. One species of doubtful position (probably and Ancilla is described in Appendix 1. (auth)