. The Cyathaspididae; a family of Silurian and Devonian jawless vertebrates. Cyathaspididae. DENISON: THE CYATHASPIDIDAE 379. Fig. 121. Vernonaspis bamberi, anterior part of dorsal shield of type (from Denison, 1963); Princeton 17081 (X 4). lep, lateral epitegum; or, orbit; pm, pineal macula; rep, rostral epitegum. are posterior transverse ridges, commonly broken into short lengths, and anterior ridges parallel to the anterior edge. In the postrostral field transverse ridges in the type (fig. 120, prf) curve back into longi- tudinal central ridges; in Princeton 12922 the ridges of the postrost
. The Cyathaspididae; a family of Silurian and Devonian jawless vertebrates. Cyathaspididae. DENISON: THE CYATHASPIDIDAE 379. Fig. 121. Vernonaspis bamberi, anterior part of dorsal shield of type (from Denison, 1963); Princeton 17081 (X 4). lep, lateral epitegum; or, orbit; pm, pineal macula; rep, rostral epitegum. are posterior transverse ridges, commonly broken into short lengths, and anterior ridges parallel to the anterior edge. In the postrostral field transverse ridges in the type (fig. 120, prf) curve back into longi- tudinal central ridges; in Princeton 12922 the ridges of the postrostral field are antero-posteriorly and diagonally arranged, and in Prince- ton 18004 there are irregular convolutions. In the ventral shields referred here, the dentine ridges are slightly coarser (7-8 per mm.). The anterior edge has a median concavity, and the posterior edge has a slight median lobe in PF 855, though this is absent in PF 3646. The ridges are mainly longitudinal, but radiate anteriorly toward the antero-lateral corners. One branchial plate (New York State Mus. 9618) is referred here. It is mm. long, has a maximum depth of mm., and has nearly 10 dentine ridges per millimeter. The ridges are predominantly longitudinal and mostly flat-topped, but are sharp-crested near one edge. This plate is bluntly terminated at the anterior end and tapers toward the posterior end. Vernonaspis bamberi Denison. Figure 121. Vernonaspis bamberi Denison, 1963, Fieldiana: Geol., 14, no. 7, pp. 110-113, figs. 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 Denison, Robert H. (Robert Howland), 1911-1985; Chicago Natural History Museum. Chicago : Chicago Natural History Museum Press
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