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The distribution of all known Cambrian echinoderm taxa, encompassing both articulated specimens and taxonomically diagnostic isolated ossicles, is documented for the first time. The database described by 2011 comprises 188 species recorded from 65 formations from around the world. Formations that have yielded articulated echinoderms are unequally distributed in space and time. Only Laurentia and West Gondwana provide reasonably complete records at the resolution of Stage. The review of the biogeographical distributions of the eight major echinoderm clades shows that faunas from Laurentia and Northeast Gondwana (China and Korea) are distinct from those of West Gondwana and Southeast Gondwana (Australia); other regions are too poorly sampled to make firm palaeobiogeographical statements. Analysis of alpha diversity (species per formation) shows that diversity rose initially to Cambrian Stage 5, declined into Guzhangian and Paibian before returning to Stage 5 levels by the end of the Cambrian. This pattern is replicated in Laurentia and West Gondwana. We show that taxonomically diagnostic ossicles found in isolation typically occur significantly earlier than the first articulated specimens of the same taxa and provide important information on the first occurrence and palaeobiogeographical distribution of key taxa, and of the phylum as a whole.Supplementary material:Articulated Cambrian echinoderms and Isolated plates of Cambrian echinoderms are provided at:http://www.geolsoc.org.uk/SUP18668

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Hughes, N. C. & Jell, P. A. 1992 07 15: A stdlislical/compuler‐graphic technique for assessing variation in tectonically deformed fossils and its application to Cambrian trilobites from Kashmir. A combined approach using statistics and computer graphics can help resolve patterns of morphological variation in tectonically deformed fossils. Bivariate analyses and Principal Components Analysis can be used to identify a generalized strain vector in populations of deformed fossils, the identification of which permits discrimination of biological and tectonically induced variation. Results can be used to determine the number of taxa and growth relationships within the population. Statistically resolved taxa can be compared with species described from other areas using computer‐aided shape restorations. Application of these techniques to a sample of trilobite cranidia from the Cambrian of Kashmir demonstrates that the variation of characters used to diagnose several genera and species are ontogeny‐ or deformation‐controlled. Seven previously described species of Saukia, Prosaukia, Hundwarella and Anomocare are best considered as a single species, Hundwarella personara. These results suggest a Middle Cambrian age for the fauna, which has affinities with other faunas described from India and northern China. Hundwarella personara shows a pattern of developmental flexibility similar to that seen in other Cambrian trilobites. Morphometrics, computer‐aided restoration, deformed fossils, allometry, trilobites, Cambrian, Kashmir, developmental flexibility.