. Bulletin of the British Museum (Natural History), Geology. PALAEONISCOID FISHES AND THE CHONDROSTEI l63 The fins are always poorly preserved. No specimen I have examined shows a pectoral fin, while all that can be said about the anal is that it only possessed a few rays. The pelvics have some seven or eight stout rays and the dorsal about fifteen. The scales are very large in porportion to body size, at the deepest part of the body numbering between eight and nine rows. Scale structure. The structure of the scale (Text-fig. 15) is almost identical with that of Pseudogonatodus macrolepis (Tra
. Bulletin of the British Museum (Natural History), Geology. PALAEONISCOID FISHES AND THE CHONDROSTEI l63 The fins are always poorly preserved. No specimen I have examined shows a pectoral fin, while all that can be said about the anal is that it only possessed a few rays. The pelvics have some seven or eight stout rays and the dorsal about fifteen. The scales are very large in porportion to body size, at the deepest part of the body numbering between eight and nine rows. Scale structure. The structure of the scale (Text-fig. 15) is almost identical with that of Pseudogonatodus macrolepis (Traquair) even down to the large number of fibres of Sharpey. The bone cells are however larger and considerably fewer in Drydenius Fig. 15. Drydenius molyneuxi (Traquair). Dorso-ventral cross section through mid-lateral scale. X90. From Locality and horizon. The lectotype came from the North Staffordshire Coal Measures (Westphalian C), in the Deep Mine Ironstone at Longton, Staffordshire. It is also recorded from Broadsfield, Fenton. On the Continent it has been recorded from the Upper Carboniferous of France (Pruvost 1919 : 425), Belgium (Pruvost 1930 : 130 ; Heide 1943 : 39) and, doubtfully, from Aachen, Germany (Vangerone 1958 : 472). Family TRISSOLEPIDIDAE Fric 1893 1936 Gymnoniscidae Berg : 345. Diagnosis. Trunk fusiform ; dorsal fin in front of anal fin. Fin rays of all fins relatively few, articulated but not distally bifurcating. Suprascapular large; suspensorium upright or nearly so ; snout rounded ; teeth prominent on both jaws. 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 British Museum (Natural History). London : BM(NH)
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