. Revision of the Amphibia and Pisces of the Permian of North America. orsal and anal. No. 7935 Am. Mus. Texas. (Fig. 56 a.) 174 AMPHIBIA AND PISCES OF THE PERMIAN OF NORTH AMERICA This species is inadequately known, having been described from exceed-ingly fragmentary material. The scales agree most nearly, in size and orna-mentation, with those of Platysomus and the species may provisionally be leftin that genus. In Benedenius the scales are not nearly so deep. In the fewscales in which the external ornamented layer is preserved, it is seen that theornament agrees well with that of Platysomus
. Revision of the Amphibia and Pisces of the Permian of North America. orsal and anal. No. 7935 Am. Mus. Texas. (Fig. 56 a.) 174 AMPHIBIA AND PISCES OF THE PERMIAN OF NORTH AMERICA This species is inadequately known, having been described from exceed-ingly fragmentary material. The scales agree most nearly, in size and orna-mentation, with those of Platysomus and the species may provisionally be leftin that genus. In Benedenius the scales are not nearly so deep. In the fewscales in which the external ornamented layer is preserved, it is seen that theornament agrees well with that of Platysomus, consisting of very fine, parallel,slightly undulating lines, crossing the scale at a slight angle to its verticalaxis (plate 30, fig. 7). The flank scales have a depth of about three timestheir width. Copes original description may here be quoted. Original description 0/ species: The scale-series tend slightly backwardfrom the vertical below, without distinct curvature. The scales on thesides in front are about five times as deep as long, and they graduate in size. Fig. 56.—Platysomus ptdmaris Cope. A. Imperfect fish in a nodule, natural size. No. 7935 Am. Mus. Texas. B. Scales, natural size. One of the fragments representing the type specimen. No. 7281 Am. Mus. Texas. to the lowest undivided row, where they are about twice as deep as small scales of the inferior row are twice as deep as long, and theirdepth is about half that of the scales of the next series above them. Thesculpture of the scales consists of narrow vertical ridges, which are curvedslightly backwards below. About ten may be counted, crossing a trans-verse bone on each scale. Each of the narrow scales of the inferior rowpossesses a median angular keel which extends from the anterior edgedownwards and backwards, but which does not reach the posterior edge ofthe scale. The external face of the clavicle is vertically striate like thescales, and horizontally striate on the recurved portion. The intercla
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