. Bulletin of the British Museum (Natural History), Geology. LATE CAMPANIAN-MAASTRICHTIAN ECHINOIDS 131. -M Fig. 8 Camera lucida drawing of an interambulacral plate of Rhabdocidaridae gen. et sp. indet., BMNH EE3438. Scale bar = 5 mm. platform while the mamelon itself is rather small (1-2 mm diameter) and has a large central perforation. The primary tubercle lies subcentrally on the plate with a broad adradial and interradial platform on either side. The broad zones outside the areole of the primary tubercle have a few scat- tered secondary tubercles preserved, but are otherwise too abraded to
. Bulletin of the British Museum (Natural History), Geology. LATE CAMPANIAN-MAASTRICHTIAN ECHINOIDS 131. -M Fig. 8 Camera lucida drawing of an interambulacral plate of Rhabdocidaridae gen. et sp. indet., BMNH EE3438. Scale bar = 5 mm. platform while the mamelon itself is rather small (1-2 mm diameter) and has a large central perforation. The primary tubercle lies subcentrally on the plate with a broad adradial and interradial platform on either side. The broad zones outside the areole of the primary tubercle have a few scat- tered secondary tubercles preserved, but are otherwise too abraded to retain any evidence of fine tuberculation that may have been present. It is clear from the distribution of the tubercles that are preserved that these regions were covered in a rather heterogenous and open array of various-sized tubercles. Remarks. The broad plates, confluent areoles, perforate crenulate tubercles and heterogeneous secondary tubercula- tion show this to be a member of the Rhabdocidaridae. It is impossible to place this specimen in any genus on the basis of such incomplete material. However, it most probably repre- sents a species of Rhabdocidaris itself, judging from the size of the specimen and the coarseness of the secondary tubercu- lation. Family CIDARIDAE Gray, 1825 Tribe CIDARINI Gray, 1825 Subtribe PHYLLACANTHINA Smith & Wright, 1989 Genus PRIONOCIDARIS Agassiz, 1863 Prionocidaris morgani (Gauthier, 1902) PI. 1, figs 2-4; Fig. 9B 1902 Rhabdocidaris (Leiocidaris) morgani Gauthier: 145, pi. 20, figs 3-6. 1989 Cidaris cf. scabra Gauthier; Ali: 398, fig. Types. The syntypes are the two specimens described and figured by Gauthier. One is a more or less complete test 35 mm in diameter, the other an interambulacral segment. The whereabouts of this material is unknown: the specimens are not in the Morgan collection in the Museum National d'Histoire Naturelle, Paris. Material studied. Two specimens: BMNH EE3433, from the scree derived from the lowest be
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