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Seite 56 - Gastrioceras richardsonianum is by no means a typical representative of the genus, and I have been in some doubt as to whether it should be placed in Gastrioceras at all, rather than in Goniatites ss It is narrower than the typical species of the genus, with a more highly arched venter and a narrower umbilicus, and it lacks the characteristic lateral nodes. Except for the umbilicus, which is somewhat...
Seite 8 - Asterocalamites scrobirulatus and the single minute fern pinnule, is more or less macerated and obscure, the collection consisting chiefly of drift-rounded or comminuted and more or less macerated bits of stems roots, and bark, of no value except as showing that they fall within the epoch of vascular or woody plants (post-Silurian). The material is not of a nature or state of preservation to justify anything like a close correlation. The plant beds are Carboniferous. It is probable that they belong...
Seite 19 - Orbiculoidea appears to be that, so called, of residues, a system open to serious objection, and much more frequently found in use among botanists than zoologists. I believe that the rule among the latter, °Geol. Survey New York, Pal., vol. 8, pt. 1, 1892, p. 160. that unless a genotype is selected by the author the first-named species shall be employed, is far preferable, and I propose to apply it in this case.
Seite 66 - The direction of these lines is sinuous — concave over the ventral portion, then convex, with another reentrant curve half way toward the umbilicus. The venter, which is almost free from transverse costae, is crossed by extremely fine, delicate revolving striae, so faint that they might readily be overlooked even with a moderately strong hand lens. These revolving striae are continued laterally until they become implicated with the transverse wrinkles or plications, to which, however, they are...
Seite 5 - ... the problems presented by the Caney shale are peculiarly baffling. They involve two distinct areas in Oklahoma, and in their relations to other regions ramify extensively. The Caney shale occurs in numerous exposures through the Arbuckle and Ouachita mountains, in the central parts of the Choctaw and Chickasaw nations, respectively. It consists of black and blue argillites with local sandy strata in the upper part, and has a maximum thickness of more than 1,000 feet. While most of the Caney is...
Seite 13 - Prominent among the classes of organisms which are omitted are the plants, of which there are sometimes abundant though ill-preserved vestiges. These oftenest take the shape of impressions or replacements of wood or stems, and they frequently occur in immediate association with the goniatites and other cephalopods. Another neglected type is the fishes, represented not only by teeth but by what appear to be fragments of bone. In this connection may be mentioned agglomerations of organic fragments,...
Seite 18 - The method here employed of determining the generic content of Orbiculoidea appears to be that so called, of residues, a system open to serious objection, and much more frequently found in use among botanists than zoologists. I believe that the rule among the latter, that unless a genotype is selected by the author the first-named species 'Pal. NY, Vol. VIII, pt. I, p. 126, fn and p. 178. shall be employed is far preferable, and I propose to apply it in this case.
Seite 44 - Shell rather small, long, and very gradually tapering. The type specimen has a length of 52 mm., with a diameter above of 5£ mm. and below of 4 mm. The section is circular and the siphuncle central. The septa are moderately far apart, the interseptal distance at any point being to the diameter about as 1 to 1|, varying almost to the ratio of 1 to 2 in young specimens. The largest specimen observed has a diameter of 12 mm. The surface is apparently entirely smooth. This species rather closely resembles...
Seite 22 - ... is described as subcircular or longitudinally elliptical, and this specimen closely resembles Weller's type specimen, as shown by his figures. The only difference which I am able to point out is that the apex is a trifle more centrally situated than in the type. Weller states that L.

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