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Three lines of evidence are reviewed that suggest conodont animals contained multielement conodont assemblages in life. Reconstruction of the original multi-element assemblages of conodonts from the Cleistopora (K) and Zaphrentis (Z) Zones of the North Crop of the South Wales Coalfield is attempted using the Centclass programme on a Control Data 3600 computer. Two methods are described which are of use in assemblage reconstruction. Polythetic cluster analysis, first developed for use in ecological surveys, provides dendrograms from which the level of association of individual elements may be determined. This indicates common occurrences of elements and can be supplemented by comparisons of total stratigraphic range and relative frequency of elements. Thirteen groups are recognized which are compared with assemblage models based on assemblages preserved in situ on shale bedding planes. Group 8 compares with a basic duboisellid (Class C) type of assemblage. Groups 5 and 6 do not appear to represent meaningful groups. All other groups represent either complete or partial Lochreia type Class A assemblages.
