The Triassic Crinoids from New Zealand, collected by Dr. C. T. Trechmann

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Abstract
Dr. Trechmann has kindly presented to the British Museum (Natural History) a stem-fragment and a piece of calcareous sandstone containing imprints of various columnals, and has asked me to furnish some notes on them. Since these are the first Triassic crinoids to be described from New Zealand, their adequate description seems warranted, despite their fragmentary condition. All are believed to represent new species. In 1909 most of the Triassic crinoids known up to date were discussed by me in ‘Triassic Echinoderms of Bakony,’ 1 and the terminology here employed is explained in that memoir. Since then the only professedly new forms made known are those contained in Clark & Twitchell, 1915. ‘The Mesozoic & Cenozoic Echinodermata of the United States’ (U.S. Geol. Surv. Monogr. liv). These, therefore, are discussed here at greater length than the better-known European species, and for one of them a new specific name is proposed. [Mr. G. C. Martin, in a paper on ‘Triassic Rocks of Alaska,’ published December 1916 (Bull. Geol. Soc. Amer. vol. xxvii, pp. 685–718), but not received here until June 1917, records specimens of ‘ Pentacrinus .’ These, which belong to two new species of Isocrinus , are also described and compared.] Entrochus undatus, sp. nov. (Figs. 1 & 2, p. 248.) Diagnosis.— Trochitæ with smooth, faintly convex side-faces; ratio of heights to diameter circa 0·18; joint-face with about 25 coarse ill-developed ridges, radiating from the centre about halfway to the periphery, where they merge into a few broad, irregular

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