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Show APPENDIX E.- PALEOBIOLOGY. 409 » i • B R A C H I O P O D A . . TEBEBBATULA SUBTILITA. ' PLATS- II. FIG. lab, Sab. Gibbous, obovoid; valves nearly equal, convex;' teak of^ the dorsal valve elevated, incurved, and perforated at the ap& c; a mesial depression commencing iust below the centre and extending to the front, which is produced and elevated, filling a broad sinus in the ventral valve; surface masked by strong concentric striae, or lines of growth, with faint, often almost imperceptible radiating striae. • ^ , • / ^ ' . * Fig; 1 a, a young individual. Fig. 1 b, an individual of the ordinary size and form. Fig. & a, a xrfore gibbous form. Fig. 2 b, profile view of the preceding. / Fig/ 2 c, front view of the Same. ' j , '; Loc- Missct^ ri River, nea, r: Weston. , < i • » V SPIRIFfcR HfcMII> LICATA. ' K '* s P* ATI II. fcw. Sab. J. .•".. » < , Shell gibbous; ventral valve^ more elevated, " beaks nearly equal: entire surface marked by finely radiating- strata; each valve, with Iibout three plications on each . side of the mesial Qinus and elevation, which plications extend halfway. from the base to the beak, leaving the upper half . of the shell marked only' by fine striae; antprior portion of the dorsal valve " produced in a long extension, . tfhich fills a. deep angular sinus in the ventral valve. Fig. 3 a, view of the dorsal valve,, which, from distortion, shows the beak ef the ventral valve projecting above it. Fig. 3 b, front view of the same specimen. Loc. Missouri River, near Weston. , V' SPIRIFKB OCTOPLICATAT , PLATI H Fio^ 4ab. ' The specimens figured appear to be young individual*, a^ td jnaj probably belong to this characteristic carboniferous' species. Fig. 4 a, this specimen has'suffered from lateral pressure, causing an unnatural extension of the beak. |