. Acadian geology [microform] : the geological structure, organic remains and mineral resources of Nova Scotia, New Brunswick and Prince Edward Island. Geology; Paleontology; Geology; Geology; Geologie; Paléontologie; Géologie; Géologie. â Il ; â :\ 4 2 â 1 â i 1 1 r ^^ 1 k 'i i w 596 THE UPPKR 8ILU1UAN. ventral valve variably convex, and often showing a flattened or slightly concave space down the middle of the shell; cardinal margin ornamented by four or five minute spines on each side of the beak; cardino-lateral margins often a little wrinkled; surface finely striated, stria; flexuous,
. Acadian geology [microform] : the geological structure, organic remains and mineral resources of Nova Scotia, New Brunswick and Prince Edward Island. Geology; Paleontology; Geology; Geology; Geologie; Paléontologie; Géologie; Géologie. â Il ; â :\ 4 2 â 1 â i 1 1 r ^^ 1 k 'i i w 596 THE UPPKR 8ILU1UAN. ventral valve variably convex, and often showing a flattened or slightly concave space down the middle of the shell; cardinal margin ornamented by four or five minute spines on each side of the beak; cardino-lateral margins often a little wrinkled; surface finely striated, stria; flexuous, dichotomising and increasing by interstitial addition, so that there are more than 100 on the margin of the shell; striai increasing in size below the umbo; concentric striie fine, close, rounded and slightly undulating. Fig. 198. Crania AcaiUensia. e M Fig. 199. Chonetes Nora iScotica, and portions magnified. Fig. 200. CJionetcs leiiiiistrintii. Fig. 201. Tre m a tosjjira A Fig. 202. Leptocueh'u intermedia. Dorsal valve moderately concave; stria much stronger below tin; middle of the shell and sometimes bifurcating toward the margin. This species resembles in form the Clionetef^ cornuta of the Clinton group of New York, but is a much larger and more ventricose .shell; the strife are proportionally less numerous and more closely arranged, the interstices being less than the stria;, while in the C. cornuta i\u' interstices arc wider than the stria;, and tlic latter increase only by interstitial additions below the middle of the shell. A stronger and more elevated stria often marks the median line from beak to base of the ventral valve. Arisaig, East River, Nictaux, coll. J. W. D. Chonetes tenuistriata, Hall (Fig. 200). Shell semi-oval, twice as wide as long; ventral valve moderately convex, hinge-line equalling the width of the shell; surface marked by fine, even, closely arranged stria;, which apparently increase only by interstitial additions, and an- not fl
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Keywords: ., boo, bookcentury1800, booksubjectgeology, booksubjectpaleontology