. First[-fourth] annual report of the Geological survey of Texas, 1889[-1892] Edwin T. Dumble, state geologist. RAS. This genus has been sufficiently described in Genera of Fossil Cephalopods*Ephippioceras divisum. Nautilus divisus, White and St. John, Descrip. Fossils, etc., Trans. ChicagoAcad. Sciences, I, p. 124. Loc. Kansas, near Oswego. Coll. Nat. Mus. from Dr. Newlon. Texas, in Coll. Geol. Survey, and from Kansas City, Mo., in Coll. Dr. New-bery, N. Y. Lower Coal Measures. Fig. 52-54, one-third of the natural size. The fragment in hand is so much larger than any other specimen of thisgen
. First[-fourth] annual report of the Geological survey of Texas, 1889[-1892] Edwin T. Dumble, state geologist. RAS. This genus has been sufficiently described in Genera of Fossil Cephalopods*Ephippioceras divisum. Nautilus divisus, White and St. John, Descrip. Fossils, etc., Trans. ChicagoAcad. Sciences, I, p. 124. Loc. Kansas, near Oswego. Coll. Nat. Mus. from Dr. Newlon. Texas, in Coll. Geol. Survey, and from Kansas City, Mo., in Coll. Dr. New-bery, N. Y. Lower Coal Measures. Fig. 52-54, one-third of the natural size. The fragment in hand is so much larger than any other specimen of thisgenus yet found that its size alone-is characteristic. The length of the in-complete living chamber is 195 mm. measured along the centre of the abdo-men; the breadth of the same at the larger end is about 200 mm. through theumbilical shoulders, and at the smaller end through the second septum about118 mm. About two air chambers are left upon this fragment and a part ofa third. The whorl is kidney shaped in transverse section when looked atfrom the surface of the septa. The abdomino-dorsal diameter on the side. Fig. the umbilical shoulder is 59 mm., while the same diameter takenthrough the centre of the whorl is only 48 mm., the transverse diameter be-ing, as noted above, 118 mm. Notwithstanding the large size of the livingchamber the form is quite as flattened as it is in the specimen of figured by DeKoninck in his Calcaire Carbonifere,f and there isalso a similar depressed area, or broad shallow zone, running longitudinallyalong the venter. It is probable that no other species of nautiloid increaseslaterally more rapidly by growth than this one. The transverse measure-ments as given above are so large and the aspect from behind is such as tolead people to speak of these fossils as petrified skulls. The dorsal impression *Op. cit., p. 290. fAnn. du Mus. Roy. de Belgique, II, PI. 9, Fig. 1.
Size: 2173px × 1150px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., boo, bookcentury1800, booksubjectgeology, booksubjectpaleontology
