In this country the species which at one time or another have been assigned to the genus Platycrinus amount to a considerable number. From the works of J. S. Miller, J. Phillips, A. Goldfuss, T. and T. Austin, F. McCoy, de Koninck and Le Hon, etc., one might make up a list of well over a score of species, but to identify specimens from the British Carboniferous limestones with the figured or described species is a very difficult matter. This is due chiefly to the poorness of the illustrations of the species concerned or, when the figures are passably good, to the lack of prominence given to the more important characters of the calyx. Two at least of McCoy's species and one of Phillips's are not illustrated at all. There is also some confusion regarding certain species which seem to have been figured more than once under different names. In the process therefore of identifying specimens it soon becomes evident that few of the species have been placed on a satisfactory basis and that as a group the British Platycrinidae is much in need of revision.