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70 Class—ASTEROIDEA. Obs.—Stavfisli arc not known to occur either in the Carboniferous or Permo-Carboniferous rocks of Western Australia, or Queensland. Order—Encrinasterise. Family—FA LJEA STFRIDJE. Genus—PALiE ASTER, Hall, 1852. (Pal. New York, ii. p. 247) Obs.—The genus Falceaster ranges from the Upper Silurian to the Carboniferous, hut its representation in rocks of the latter period is far more limited as regards species than in those of the former. The three species from the Permo-Carboniferous of New South Wales, now referred to Falceaster, although possessing the general features of the genus, differ in an important particular from Hall’s original types, P. matutina 1 and P. eucharis. 2 In both of these, and in other Silurian and Devonian forms, the adambulacral plates, bordering the ambulacral avenues, are small and quadrangular, followed by large transverse marginal plates. In our Permo- Carboniferous species, on the contrary, the adambulacral plates (PI. XV, Pig. 4) are transversely elongated, and occupy nearly the whole of the actinial surface on each side the avenues. 3 The marginal plates, in contra distinction to those of Hall’s Silurian species, are here smaller and sub dorsal in position (PL XIV, Pig. 2). The question now presents itself, of what value in a classificatory sense is this character ? Hall lays particular stress on the position of these plates on the actinial side of Falceaster. He says 4 it “ has two ranges of plates on each side of the ambulacral groove; marginal and adambulacral plates on the lower side, besides ambulacral or poral plates. The upper or dorsal side has three or more ranges of plates.” In the case of our specimens, only one set of plates, excepting those of the ambulacral grooves, are, as before stated, absolutely actinial; the marginal are strictly so, or, at the least, sub-dorsal. Under these circumstances, I 1 Twentieth Ann. Report N. York State Cab. Nat. Hist., 1867, p. 283, t. 9, f. 2. 2 Loc. cit., p. 287, t. 9, f. 3, 3*, 3 a , and 4. 3 This feature is also visible in De Koninek’s figure, Foss. Pal. Nouv.-Galles du Sud, 1877, Pt. 3, t. 7, f. 6*. ‘Twentieth Ann. Report N. York State Cab. Nat. Hist., 1867, p. 283.