. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. SOUTHERN AFRICAN RAJIDAE (CHONDRICHTHYES, BATOIDEl) 15 (5) >^W^^ The term was introduced by Ishiyama (1958: 203) as 'a component located on the distal portion of the ventral lobe, having a soft projection like the foot of a bivalve mussel'. He relates this structure directly to the ventral terminal cartilage. It can be seen that in those species in which the funnel is present (Ishiyama 1958: fig. 4) it always overlies the 'spur', where this is present, on the inner ventral surface. Examination of
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. SOUTHERN AFRICAN RAJIDAE (CHONDRICHTHYES, BATOIDEl) 15 (5) >^W^^ The term was introduced by Ishiyama (1958: 203) as 'a component located on the distal portion of the ventral lobe, having a soft projection like the foot of a bivalve mussel'. He relates this structure directly to the ventral terminal cartilage. It can be seen that in those species in which the funnel is present (Ishiyama 1958: fig. 4) it always overlies the 'spur', where this is present, on the inner ventral surface. Examination of the corresponding cartilages (Ishiyama 1958: fig. 12) reveals that in these species the only cartilage which can possibly overlie the accessory terminal ('spur') is the distal end of the ventral marginal. Furthermore, Ishiyama (1958) introduces the term claw for the species Rhinoraja odai and Rhinoraja longicauda, relating this to a modification of the accessory terminal cartilage. However, he shows (1958: fig. 11) that the accessory terminal in these species is a single cartilage, which is flat and sharp- edged and quite unlike the external claw. Again, examination of the figures (Ishiyama 1958: fig. 12) shows that the cartilage which overlies the accessory terminal (knife), and is extended distally, is the ventral marginal Fig. 11. Anacanthobatis americanus. Lateral view of right clasper opened to show structural features of the glans. Scale 1,0 cm. g —clasper groove; ps — pseudosiphon; rh — rhipidion; sp —spike; st —sentinel. This means therefore that neither the ventral terminal nor the accessory terminal can be related to the term funnel or claw, and that clearly the ventral marginal is the associated cartilage in both cases. Further confusion is added because the claw in Rhinobatos schlegeli Rhinobatos annulatus (Ishiyama 1958: figs 13, 14) is formed by the accessory terminal Please note that these images are extracted from scanned p
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
