Circothecidae

Circothecidae
Scientific classification
Kingdom:	Animalia
Class:	†Hyolitha
Order:	†Orthothecida (?)
Family:	†Circothecidae

Circothecidae are a family of Cambrian problematica, sometimes attributed to the Hyolitha,¹ though some authors suggest (on the basis of no specified evidence) that they are definitely not.²

References

Brasier, M. D. (1986). The succession of small shelly fossils (especially conoidal microfossils) from English Precambrian–Cambrian boundary beds. Geological Magazine, 123(3), 237–256. doi:10.1017/S0016756800034737
Webers, G. F., & Yochelson, E. L. (1989). Late Cambrian molluscan faunas and the origin of the Cephalopoda. Geological Society, London, Special Publications, 47(1), 29–42. doi:10.1144/gsl.sp.1989.047.01.04

[1] Brasier, M. D. (1986). The succession of small shelly fossils (especially conoidal microfossils) from English Precambrian–Cambrian boundary beds. Geological Magazine, 123(3), 237–256. doi:10.1017/S0016756800034737

[2] Webers, G. F., & Yochelson, E. L. (1989). Late Cambrian molluscan faunas and the origin of the Cephalopoda. Geological Society, London, Special Publications, 47(1), 29–42. doi:10.1144/gsl.sp.1989.047.01.04

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