. Bulletins of American paleontology. Ordovician conodonts: Bergstrom and Sweet 319 and the denticle immediately in front of the cusp is distinctly smaller than others on the anterior process in many specimens. Posterior to the denticles of the anterior process is a strongl}' reclined cusp that is slightly compressed laterally and has convex lateral faces. The short posterior process bears two or three reclined, laterally confluent denticles, which decrease in size and length pos- teriorly. The denticle immediately posterior to the cusp tends to he suppressed during growth and is ultimately in
. Bulletins of American paleontology. Ordovician conodonts: Bergstrom and Sweet 319 and the denticle immediately in front of the cusp is distinctly smaller than others on the anterior process in many specimens. Posterior to the denticles of the anterior process is a strongl}' reclined cusp that is slightly compressed laterally and has convex lateral faces. The short posterior process bears two or three reclined, laterally confluent denticles, which decrease in size and length pos- teriorly. The denticle immediately posterior to the cusp tends to he suppressed during growth and is ultimately incorporated in the cusp base. No such tendency for "overgrowth" has been observed at an\- other site on either process. The under side of the element is longitudinally excavated for its full length. Beneath the anterior process, the basal cavity is shallow and narrow; below the cusp, its walls flare laterally and the en- closed cavity is more capacious. Posterior to the cusp, the basal cavity is narrow and shallow^ but it can be traced to the extremity of the short process. The sides of both the anterior and posterior process are smooth and faintly convex in most specimens. In large specimens, there is a marked constriction in one side along the upper edge of the sheath and a somewhat less conspicuous constriction in the same position on the opposite side. The prioniodina-like elements we include in Bryantodina: abrupt a- are arched, faintly bowed, individually as\aiimetric, and consist of a laterally compressed, erect to slightly recurved cusp and short an-. Text-fig. 8. A-D. Bryii/itoJi/ia? ahiupta (Branson and Mehl). E-H. Bryanio- dina? stauffrri, sp. no-v. Diagrammatic lateral views of bryantodina-like (A,B; E,F) and prioniodina-like (C,D; Ci,H) elements of these species, X Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfect
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