Maryland Geological Survey: Upper Cretaceous. 2 pts

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Johns Hopkins Press, 1916
 

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Página 35 - The credit for the first definite recognition of the Cretaceous deposits of the Atlantic Coastal Plain must be ascribed to Lardner Yanuxem.
Página 385 - Shell with the very narrow periphery truncated, and often provided with a row of compressed alternating nodes along each margin; volutions each about three-fourths embraced by the next succeeding outer one; septa with the lateral sinuses provided with more or less branched and digitate terminal divisions, umbilicus small or moderate."- — Meek, 1876.1 PLACENTICERAS PLACENTA (DeKay) Meek Plate XII A Ammonites placenta DeKay, 1828, Ann.
Página 558 - It is with some hesitation that a species of so variable a group of shells as the oysters has been proposed for a single specimen, but it has not been possible to identify it with any of the described forms, and it seems to be so distinct that it is probable that additional examples, should they be found, could be recognized without difficulty. The shell has much the general outline of the specimen referred to O. crenulimarginata by Whitfield, but that shell entirely lacks the characteristic denticulation...
Página 476 - Ixxxi, flgs. 18, 19. Description. — " Shell fusiform, whorls convex, the body whorl with about eighteen and the spiral wohrls with fifteen equidistant, flexuous, longitudinal ribs; numerous fine, revolving lines, more prominent between the ribs and somewhat obsolete on the angles of the ribs, cover the entire shell ; suture deeply impressed. The length of the largest specimen (including the two apical whorls, which are wanting) is about 20 mm.
Página 39 - America, with some remarks on the probable effect that may be produced by the decomposition of the different classes of Rocks on the nature and fertility of Soils.
Página 40 - HAYDEN, HH Geological Essays; or an Inquiry into some of the Geological Phenomena to be found in various parts of America and elsewhere.
Página 44 - TYSON, PHILIP T. Second Report of Philip T. Tyson, State Agricultural Chemist, to the House of Delegates of Maryland, Jan.
Página 491 - Conrad, 1858. Type Locality. — Owl Creek, Tippah County, Mississippi. " The dimensions of a large example, incomplete at the apex, are : Height 69 mm., greatest diameter 22 mm., apical angle about 19°, number of volutions shown 10. Suture situated in the bottom of a broad, concave, revolving channel. Surface of the volutions between the margins of the sutural channel nearly flat or slightly convex; marked by four or five strong, revolving...
Página 426 - Shell elongate, fusiform ; whorls cancellated by longitudinal and revolving ribs ; columella with one very oblique fold, and sometimes one or more smaller secondary folds. In shape this genus is not unlike the two preceding genera [ Volutoderma Gabb, and Fulgoraria Schum], but it differs from them all in having essentially a single large oblique fold.
Página 364 - The lower distal angle is acute, and there is an oblique groove and a short keel bordered with small tubercles near it on the outer face. The upper proximal angle is produced backward. The inner face has a small distal group of tubercles and some scattered pustules, both usually almost effaced. Merus subtriangular in section, the upper keel strongly arched, lower keel nearly straight and more strongly serrate, the middle of the very convex outer surface granulose, with two rounded tubercles at the...

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