. Bulletin of the British Museum (Natural History), Geology. devoid of a dermal bone covering. In fact the frontals form the usual trough for the supraorbital sensory canal in this region. There is no sound evidence, either, for the kidney-shaped nasals of Saint-Seine's description. The parietals are large, roughly triangular bones. The anterior border, which corresponds to the greatest width, is overlapped by the frontal along a shghtly sinuous suture. The anterolateral border of the parietal forms a short suture with the dermosphenotic. The posterolateral border forms two large embayments as
. Bulletin of the British Museum (Natural History), Geology. devoid of a dermal bone covering. In fact the frontals form the usual trough for the supraorbital sensory canal in this region. There is no sound evidence, either, for the kidney-shaped nasals of Saint-Seine's description. The parietals are large, roughly triangular bones. The anterior border, which corresponds to the greatest width, is overlapped by the frontal along a shghtly sinuous suture. The anterolateral border of the parietal forms a short suture with the dermosphenotic. The posterolateral border forms two large embayments as it converges towards the midhne; in contrast with other members of the family, the parietal enclosed only a very short section of the supratemporal commissure on either side of the midline. The surface of the bone is covered with an even layer of ganoine which is interrupted by the anterior and middle pit-hnes. The middle pit-line forms a short groove close to, and parallel with, the posterior edge of the parietal. The anterior pit-line is equally short, extending at an angle of about 100 degrees anterolateral to the middle pit-line (Fig. 41). There is no evidence to suggest that a branch of the supraorbital sensory canal extended onto the parietal (cf Saint-Seine 1949 : fig. 84).. Fig. 41 Notagogus helenae (Thiolliere). Skull roof, as preserved in x6. Saint-Seine (1949) identified two bones in contact with the posterolateral border of the parietal: a 'supratemporal' ( dermopterotic) suturing with the anterior embayment, and an 'extra- scapular' ( supratemporal) posteriorly. This region of the skull, however, is in fact occupied by a single, large, triangular bone; Saint-Seine has mistaken for a suture the collapsed tube of the lateral part of the supratemporal commissure which passed through this element. This condition is unknown in other macrosemiids. Since this bone houses both the supratemporal commissure and the cephalic division of the main lateral line,
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