. Annual report. New York State Museum; Science; Science. SOME NEW DEVON IC FOSSILS I57 imate; it bears n or 12 segments and its apex is not abrupt but merges into a low median ridge continued to the end of the tail. The terminal spine is little more than a broad and short rather obtuse expansion. The surface of the test is finely granulate ex- cept for a few scattered coarser pustules on the axis. The speci- mens average 26 mm in length and 29 mm in width. This style of pygidial structure with strongly bifurcate pleural ribs is represented in the faunas of the early Devonic elsewhere by such
. Annual report. New York State Museum; Science; Science. SOME NEW DEVON IC FOSSILS I57 imate; it bears n or 12 segments and its apex is not abrupt but merges into a low median ridge continued to the end of the tail. The terminal spine is little more than a broad and short rather obtuse expansion. The surface of the test is finely granulate ex- cept for a few scattered coarser pustules on the axis. The speci- mens average 26 mm in length and 29 mm in width. This style of pygidial structure with strongly bifurcate pleural ribs is represented in the faunas of the early Devonic elsewhere by such species as D. bisignatus Clarke (Oriskany) and D. dentatus Barrett (Oriskany). It is probable that the cephala of all have a crenulated or dentate border as D. den- tatus and its associate D. d o 1 p h i Clarke are known to have. Lozver Devonic. Grande Greve and Indian Cove, P. Q. Dalmanites perceensis nov. The parts found of this species are separated pygidia and cra- nidia. In the latter the frontal lobe is gently rounded and de- pressed ; the first and second lateral lobes well fused at their ex- tremities ; the surface of the frontal lobe coarsely papillose. The. perceensis pygidium is broadly triangular, but little arched at the sides; the lateral margins rounding in full curves and the tail spine short, acute and upturned; the axis has straight regularly converging dorsal furrows and its width is less than two thirds the width of each pleura. It bears 18-20 broad flat directly transverse annula-. 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 New York State Museum. Albany : University of the State of New York
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectscience, bookyear1902
