. Bulletin of the British Museum (Natural History). OSTEOLOGY OF THE D ENTICI PIT I D AE 247 FRs^ \. 1 mm. Fig. 24. Articulation of the pectoral fin rays (left side), seen from above with the anteroposterior axis of the fin aligned horizontally. turn articulates with a capstan-shaped proximal element associated with the mid- ventral area of the scapular margin. The ninth to the eleventh pectoral rays share a common distal radial which, in turn, articulates with an elongate, rectangular proximal element meeting the coracoid immediately below the scapulo-coracoid junction. In one specimen examin
. Bulletin of the British Museum (Natural History). OSTEOLOGY OF THE D ENTICI PIT I D AE 247 FRs^ \. 1 mm. Fig. 24. Articulation of the pectoral fin rays (left side), seen from above with the anteroposterior axis of the fin aligned horizontally. turn articulates with a capstan-shaped proximal element associated with the mid- ventral area of the scapular margin. The ninth to the eleventh pectoral rays share a common distal radial which, in turn, articulates with an elongate, rectangular proximal element meeting the coracoid immediately below the scapulo-coracoid junction. In one specimen examined, there is a twelth ray, very short and fine; it too shares the same radial as the ninth to eleventh rays. Dorsal elements of the pectoral girdle. The extrascapular, which should be included here, has already been discussed (p. 235) in connection with skull roofing bones. Of the two remaining bones, the supracleithrum is firmly attached to the cleithrum. It is a large, flat bone, kidney-shaped in outhne with the concave side directed forward. The tube carrying the laterosensory canal from the body passes obhquely across the supracleithrum. It opens into the laterosensory tube of the posttemporal where the latter overlaps the anterodorsal half of the supracleithrum. The posttemporal (Text-fig. 25) has a large, nearly rectangular and flat body, but with the anterodorsal angle greatly produced into a substantial, flattened spine. The tip of this spine is firmly attached to the pterotic and the epiotic. The medial limb of the posttemporal is partly ligamentous; only about the proximal half is ossified. Distally, the ligamentous section is firmly associated with the pterotic at a point sMghtly below the horizontal semicircular canal, just anterior to the pterotic- exoccipital junction. The laterosensory tube runs near the ventral margin of the bone, and joins with the lower limb of the extrascapular laterosensory tube. A single row of odontodes runs along at least part of the post
Size: 1686px × 1483px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., 1968, boo, bookauthorbritishmuseumnaturalhistory, bookcentury1900
