. Bulletins of American paleontology. 490 Bulletin 116 572 Ohavactociras baeri Foertite, 1924, Dciiisoii Uiiiv. Bull., bei. i<;!b., Jour., vol. 20, p. 235, pi. 31, fifT. 1; pi. ;;!2, fig. lA-B; pi. 33, fig. lA-B; pi. 34, %. lA-B, Figure 22. Charo-ctoceras hacri (Meek .-ind Wortlicn). A. Aperture, seen from the ventral side. From Foerste, 1924, pi. 32, fig. 1. B. Same speeimei), ventral view, showing gerontic ciuncra:- ixi auoral emi of phrag- mocono. C. Same specimen, view, allowing the gyroconic condi- tion of the living cliamber. D. Section through phragniocone showing form
. Bulletins of American paleontology. 490 Bulletin 116 572 Ohavactociras baeri Foertite, 1924, Dciiisoii Uiiiv. Bull., bei. i<;!b., Jour., vol. 20, p. 235, pi. 31, fifT. 1; pi. ;;!2, fig. lA-B; pi. 33, fig. lA-B; pi. 34, %. lA-B, Figure 22. Charo-ctoceras hacri (Meek .-ind Wortlicn). A. Aperture, seen from the ventral side. From Foerste, 1924, pi. 32, fig. 1. B. Same speeimei), ventral view, showing gerontic ciuncra:- ixi auoral emi of phrag- mocono. C. Same specimen, view, allowing the gyroconic condi- tion of the living cliamber. D. Section through phragniocone showing form of siphuncle. E. Diagrammatic cross section. F. Projection of suture. A-C. After photographs of Foerste, 1924. All figures about 1/3 natural size. This is a larye coiled shell, the whorls raiiidly expandiniJ," in the early portion. There is apparently an appreciable umbilical perforation, the shell is depressed in section from the earliest portions observed, and an impressed zone appears at tlie .comple- tion of the first volution of the shell. This is retained throuirhout life with little change, until the gerontic living chamber is reached. This becomes free dorsally and apparently loses the impressed zone, though clearl}' preserved dorsums of such living chambers have not been observed. The cross section of the shell is exceedingly difficult to deter- mine, inasmuch as nearly all of the extant specimens are more or less distorted by pressure. However, it is evident that the venter is flattened, forming a rather distinct face, the sides ai*e strongly rounded laterally, becoming less curved upon approaching the dorsum, so that they become nearly flat as they approach the im- pressed zone. The impressed zone is 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 perfectly resemble the original Paleontological Research Institutio
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