. Bulletin of the British Museum (Natural History), Geology. 212 SMITH. Fig. 68 Camera lucida drawings of plating in Petalobrissas linguiformis (Peron & Gauthier). A, oral surface, BMNH EE3344; B, apical surface, BMNH EE3345; C, oral phyllode, peristomial margin at base, BMNH EE3334; D, apical disc, BMNH EE3345. Scale bars: A, B = 5 mm; C, D = 1 mm. Genus STIGMATOPYGUS d'Orbigny, 1856 Stigmatopygus pulchellusl sp. nov. PI. 27, figs 1-8; Figs 69,70 Types. Holotype BMNH EE4314, paratypes, BMNH EE3324-25, EE3329-30, EE3332-33, EE4312-13: all nine specimens were used for the biometric ana
. Bulletin of the British Museum (Natural History), Geology. 212 SMITH. Fig. 68 Camera lucida drawings of plating in Petalobrissas linguiformis (Peron & Gauthier). A, oral surface, BMNH EE3344; B, apical surface, BMNH EE3345; C, oral phyllode, peristomial margin at base, BMNH EE3334; D, apical disc, BMNH EE3345. Scale bars: A, B = 5 mm; C, D = 1 mm. Genus STIGMATOPYGUS d'Orbigny, 1856 Stigmatopygus pulchellusl sp. nov. PI. 27, figs 1-8; Figs 69,70 Types. Holotype BMNH EE4314, paratypes, BMNH EE3324-25, EE3329-30, EE3332-33, EE4312-13: all nine specimens were used for the biometric analysis given below in the description. Other material. In addition a further six specimens were collected. Occurrence. The species has been found only at Jebel Rawdah, section 2, at the following horizons: bed 14 (6); bed 19 (1); bed 21 (7); loose in scree, derived from beds 14-21 CD- Description. Tests are elongate oval in outline, with a rounded anterior and a small posterior indentation (PI. 28, figs 2-7). Tests range in length from 37 to 68 mm. Test width is 77-84% of test length (mean = 80%, SD = 1-9%, N = 9) and the widest point is slightly posterior of midlength. Test height is 41-56% of test length (mean = 47, SD = 4-9%, N = 9). The test has a depressed profile with the highest point coincidental with the apical disc and thus anterior of centre. There is a posterior notch marking the position of the periproct, and a small heel underneath the periproct in profile (PI. 27, fig. 5). The apical disc lies anterior of centre, some 32-40% of test length from the anterior border (mean = 37%, SD = 3-4%, N = 7). It appears to be tetrabasal, although the madrepores extend almost up to the start of the gonopores (Fig. 70D). There is no evidence for sexual dimorphism amongst the specimens to hand. The petals are bowed, and are widest about one third of their distance from the apex (PI. 27, fig. 7). The anterior petal has columns of equal length and the inner series of pores are almos
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