SUMMARY

A small collection of well-preserved crinoid attachment structures from the Upper Devonian Pilton Formation of north Devon indicates the presence of two distinct species. Sostronocrinus mundus (Whidborne) lived attached to an unlithified sedimentary substrate by the vertical insertion of a robust, terminal rhizoidal holdfast abetted by robust, unbranched radices oriented laterally or curved distally. There was a strong differentiation of morphology between the radicular attachment and the more proximal column, which lacked radices. Eumorphocrinus porteri (Whidborne) attached to a similar substrate by an irregularly heteromorphic, tapering radicular runner bearing branched radices that promoted permanent attachment close to the sediment surface. These radices were probably developed on at least part of the more proximal column. The highest columnals of the dististele do not bear radices and, therefore, are not nodals. The dististele was previously unknown in both of these species.

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