. Bulletin of the British Museum (Natural History), Geology. LATE CAMPANIAN-MAASTRICHTIAN ECHINOIDS 215. Fig. 70 Camera lucida drawings of plating in Stigmatopygus pulchellus sp. nov. A, oral surface, BMNH EE4312; B, apical surface. BMNH EE4314; C, phyllode plating, peristomial margin at base, BMNH EE4312; D, apical disc, BMNH EE3325. Scale bars: A, B = 5 mm; C, D = 1 mm. but appear smooth to the naked eye. Remarks. This is a very distinct species, on account of its asymmetric posterior petals and keyhole-shaped periproct. Small forms resemble Petalobrissus linguiformis (Peron & Gauthier),
. Bulletin of the British Museum (Natural History), Geology. LATE CAMPANIAN-MAASTRICHTIAN ECHINOIDS 215. Fig. 70 Camera lucida drawings of plating in Stigmatopygus pulchellus sp. nov. A, oral surface, BMNH EE4312; B, apical surface. BMNH EE4314; C, phyllode plating, peristomial margin at base, BMNH EE4312; D, apical disc, BMNH EE3325. Scale bars: A, B = 5 mm; C, D = 1 mm. but appear smooth to the naked eye. Remarks. This is a very distinct species, on account of its asymmetric posterior petals and keyhole-shaped periproct. Small forms resemble Petalobrissus linguiformis (Peron & Gauthier), but are easily distinguished from that species by their phyllode structure and periproct shape. P. linguiformis has a longitudinal periproct with a short parallel-sided anal sulcus, and also has much better developed phyllodes, with a separate series of inner occluded plates. The new species undoubtedly comes closest to the type species of Stigmatopygus, S. galeatus d'Orbigny from the late Cretaceous of Angouleme, France. Both have a very similar test shape and periproct position and shape. Unfortunately, this species is very poorly known, the original description and figures being quite inadequate by today's standards. In par- ticular its phyllode structure is unreported. Kier (1962) described the phyllode structure of another species 5. lam- berti Bessairie, from the Campanian of Madagascar, but this differs in being much wider and taller, with a much larger periproct. It also has better developed phyllodes, which are clearly bowed and comprise an outer series of some 12 pores and an inner series of 4 or 5 pores. I am therefore not certain that S. lamberti is truly congeneric with the type species 5. galeatus. Only re-study of the type (apparently lost), or topotype material will solve the problem. If the phyllode structure of 5. galeatus is similar to that of S. pulchellus, then S. lamberti should be transferred to a new genus. On the other hand, if S. galeatus proves to ha
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