The need for recognition of variable species in classification of the Jurassic Lagenidae is demonstrated by the variation in degree of coiling, cross-sectional shape, form of suture line, and other features of test morphology exhibited within individual species of lagenids from the Bathonian of England. Such variational patterns, also reported in some species from the English Liassic, probably reflect genetic response to environmental fluctuations.

You do not currently have access to this article.