. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. SOUTHERN AFRICAN RAJIDAE (CHONDRIGHTHYES, BATOIDEl) 65 only in Raja caudaspinosa (Fig. 53 F). The dorsal surface of the neurocranium is perforated by two large fonta- nelles, separated by the narrow epiphysial bridge. The most anterior of these, usually termed the anterior fontanelle, is an amalgamation of the precerebral fontanelle and the anterior supracranial fontanelle (Hamdy i960). The posterior fontanelle should therefore be correctly termed the posterior supra- cranial fontanelle (El-Tourbi &a
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. SOUTHERN AFRICAN RAJIDAE (CHONDRIGHTHYES, BATOIDEl) 65 only in Raja caudaspinosa (Fig. 53 F). The dorsal surface of the neurocranium is perforated by two large fonta- nelles, separated by the narrow epiphysial bridge. The most anterior of these, usually termed the anterior fontanelle, is an amalgamation of the precerebral fontanelle and the anterior supracranial fontanelle (Hamdy i960). The posterior fontanelle should therefore be correctly termed the posterior supra- cranial fontanelle (El-Tourbi & Hamdy 1959; Hamdy i960). In Rhinobatos halavi and Rhinobatos productus (Daniel 1934: fig. 62), the anterior fontanelle is moderately wide at its posterior end, and narrows anteriorly to run as a groove, almost to the tip of the rostral cartilage, there is no marked anterior border to the fontanelle in these species. Anterior grooving of the rostral cartilage is found only in Raja doutrei, R. pullopunctata, R. lanceorostrata and R. stenorhynchus (Fig. 50) and reaches its maximum development in R. springeri (Fig. 50 F). In these species the posterior region of the anterior fontanelle is moderately wide, while the posterior margin is produced in Raja doutrei and R. lanceorostrata (Figs 50 D, G), and evenly curved in Raja pullopunctata, R. stenorhynchus and R. springeri (Figs 50 A, E, F). In Bathyraja smithii (Fig. 49 A) the anterior fontanelle is pear-shaped, with a broad posterior region and an evenly curved anterior margin, which is not elongated to form a furrow. In Raja clavata,. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original South African Museum. Cape Town : The Museum
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
