. Geological magazine. xtends backwards for adistance equalling half the length of the spine; and the bone isevidently preserved as far upwards as its sutural connection withthe supra-clavicle, though unfortuately mutilated near the rigidlower symphysis. Of the spine itself, the National Collection comprises severalexamples, which render it possible to define its characters specimens vary considerably in size, though agreeing in everyother respect, and the beautiful fossil already mentioned is much thelargest, while one of the smaller ones (B. M. 25736) was originallyselected
. Geological magazine. xtends backwards for adistance equalling half the length of the spine; and the bone isevidently preserved as far upwards as its sutural connection withthe supra-clavicle, though unfortuately mutilated near the rigidlower symphysis. Of the spine itself, the National Collection comprises severalexamples, which render it possible to define its characters specimens vary considerably in size, though agreeing in everyother respect, and the beautiful fossil already mentioned is much thelargest, while one of the smaller ones (B. M. 25736) was originallyselected to show the form of the proximal articulation. All are ofthe ordinary laterally-compressed shape, and, when well preserved,exhibit an ornament of closely-approximated, short irregular ridges,rising at intervals into small conical bosses. In the distal half ofthe spine, the denticles upon the edges are large and recurved, butmore proximally they become much smaller, and the points inclinein the opposite direction. ff^T:. J Figs. 1 and 2. Arius Egertoni, Dixon sp., M. Eocene, Brackleshani Bay, Sussex, 3. Arius ? Bartonensis, sp. nov., XJ. Eocene, Barton Clifi, Hampshire, , median view of proximal articular end of Fig. 3. Dorsal Spine, etc.—The dorsal spine, associated by Dixon with Silurus Egertoni, corresponds so closely in the character of itsornamentation with the pectoral appendage already referred to, thatthere can be little doubt as to the correctness of the correlation. A. Smith Woodward—Eocene Sihiroid Fishes. 305 But the British Museum does not appear to possess any examplesufficiently large to have pertained to a fish of the dimensionsindicated by the pectoral arch No. 25612; and the fossil figured byDixon (No. 25735a) is one of the finest and best preserved. Thespine is remarkably straight, neither the anterior nor the posteriorborder exhibiting more than the slightest curvature, and the distaltapering is but gradual. The lower end shows the usual fac
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Keywords: ., bookcentury1800, bookdecade1860, booksubjectgeology, bookyear1864
