. First[-fourth] annual report of the Geological survey of Texas, 1889[-1892] Edwin T. Dumble, state geologist. :.v^ •??:••?>??.: ???? ..?r. ?:?-••• •.•?•/tswi, ??*/,;.•?? ? ?%&&/? 3r f. *«.».?. .^5 $ ^;?:::???:??:.: v • w:- ? ... ?:<?;,M%.M V^t?^». ?,?« , , V. : ?????. $V, .-•3 m r»fi-V • 1 .?/?>•??• y .V •»•-- « «>.*. • •• ** v- • ? i^ CORBONIFFROUS CEPHALOPODS. 355 mistakes between casts of Nautiloids and Ammonoids, if the sutures andthe young are entirely hidden. The species described below illustrates theconstancy of the sutures and the variability of
. First[-fourth] annual report of the Geological survey of Texas, 1889[-1892] Edwin T. Dumble, state geologist. :.v^ •??:••?>??.: ???? ..?r. ?:?-••• •.•?•/tswi, ??*/,;.•?? ? ?%&&/? 3r f. *«.».?. .^5 $ ^;?:::???:??:.: v • w:- ? ... ?:<?;,M%.M V^t?^». ?,?« , , V. : ?????. $V, .-•3 m r»fi-V • 1 .?/?>•??• y .V •»•-- « «>.*. • •• ** v- • ? i^ CORBONIFFROUS CEPHALOPODS. 355 mistakes between casts of Nautiloids and Ammonoids, if the sutures andthe young are entirely hidden. The species described below illustrates theconstancy of the sutures and the variability of the form. I wish also to call attention here to a characteristic not before noted in thegenus Paralegoceras. The second lateral lobes or divisions of the greatmagnoscellarian saddles occupy the umbilical shoulders in Gastrioceras,whereas in Paralegoceras these same lobes are situated on the sides of thewhorls. This distinction was noted in Gastrioceras in the description of thisgenus,* but not in Paralegoceras. The latter also has shallower umbiliciand more rounded umbilical shoulders than in Gastrioceras, the third pair ofsaddles appearing also partly on the sides. We are now able to cite anotherspecies as belonging to this interesting genu
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Keywords: ., boo, bookcentury1800, booksubjectgeology, booksubjectpaleontology
