The Mississippian succession of Ayrshire, south-west Scotland, is rich in fossil crinoids, albeit mainly preserved as fragments. Trearne Quarry is exceptional in yielding moderately common crinoid cups and thecae from certain horizons. To the two nominal taxa that have been documented hitherto, we add a further seven, all cladids with one exception. These species all come from the Blackhall Limestone of the Lower Limestone Formation (Visean, Mississippian). Nominal crinoid species identified from Trearne Quarry include Cladida: Rhabdocrinus scotocarbonarius (Wright); Ureocrinus bockschii (Geinitz); Ureocrinus globulus (de Koninck); Tyrieocrinus laxus Wright; Fifeocrinus tielensis (Wright); Hydreionocrinus formosus Wright; Parazeacrinites konincki (Bather); and Phanocrinus ardrossensis (Wright): and Diplobathrida, Camerata: Cribanocrinus baccatus (Wright). Species have distributions limited to one or a few mudrock beds. Identifiable crinoids are uncommon in massive, coral-rich reefal facies.