. Bulletin of the British Museum (Natural History), Geology. . Fig. 28 Propterm elongatus Wagner. Bases of leading edges of various fins, as preserved in A, left pelvic fin. B, left and right pectoral fins. C, anal fin. The anal fin was supported by six rays; it arises below the level of the 28th vertebral segment. Four unpaired basal fulcra extend along the proximal half of the leading edge of the fin. The third and fourth basal fulcra are cleft to within a very short distance of the pointed tip (Fig. 28C). The first fringing fulcrum is unpaired but again deeply cleft. The remain
. Bulletin of the British Museum (Natural History), Geology. . Fig. 28 Propterm elongatus Wagner. Bases of leading edges of various fins, as preserved in A, left pelvic fin. B, left and right pectoral fins. C, anal fin. The anal fin was supported by six rays; it arises below the level of the 28th vertebral segment. Four unpaired basal fulcra extend along the proximal half of the leading edge of the fin. The third and fourth basal fulcra are cleft to within a very short distance of the pointed tip (Fig. 28C). The first fringing fulcrum is unpaired but again deeply cleft. The remainder of the fringing fulcra extending along most of the length of the leading ray are paired. The base of the anal fin is short and compact, in contrast to the condition in Macrosemius, and the first ray extends beneath the caudal fin. The remaining rays become progressively shorter, to form the slightly convex profile of the hind border of the fin. (xiii) The caudal fin is deeply forked, with seven rays emanating from the axial lobe and eight, as usual, arising below this (Fig. 29B). The upper basal fulcra are deeply divided and extended basally, forming two tapering prongs which straddled and articulated with the epurals (Fig. 29A). The lateral borders of these fulcra taper posteriorly from the level of the cleft and then run parallel for a short distance before converging to a sharp point. The series continues along the uppermost fin-ray with about 13 fringing fulcra, of which the first eight (in 37099) are unpaired. The uppermost fin-ray forms a continuation of the longest axial lobe scale-row and is not inserted below the squamation, as in the type genus. The following five rays form thin, closely- grouped rods proximally which penetrate beneath the axial lobe squamation and clasp the upper hypurals. The basal part of the lowermost axial lobe ray clasps the tip of its hypural and is separated from the upper rays, although its distance from the succeeding rays is greater. Th
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