Hall, James, 1811-1898 / Geological survey of Wisconsin, 1859-1863. Palaeontology. Part third
Plate XIIa, pp. [unnumbered]-Pl. 12 a PDF (658.6 KB)
PLATE XIIa.* GOMPHOCYSTJTES TENAX, HALL. Page 352. FIG. 1. Lateral view of the upper part of the body, showing the arrangement of plates; the spiral grooves indicating the places of the sessile arms are at the upper margins of the ranges of smaller plates. The plates are more or less irregularly disposed in some parts of the body, but they appear, like others of the genus, to have a generally spiral arrangement. (Enlarged to two diameters.) 2. The summit, showing the arrangement of the spiral arms and the central aperture. The diagram is made from an imperfect specimen, and the position of the eccentric aperture could not be ascertained. GOMPHOCYSTITES CLAvUS, HALL. Page 353. FIG. 3. A fragment (natural size), showing the disposition of the spiral arms and the obtusely angular form of the body below. GomPHOCYSTIrES GLANS, HALL. Page 352. FIG. 4. Lateral view of a specimen, showing the entire form and the disposition of the spiral arms. I 5. The anterior ? view of another individual of the same species. HOIOCYSTITES ALTERNATUS, HALL. Page 865. FIG. 6. A posterior ? view of a specimen (natural size), showing the position of the eccentric aperture, form and relation of plates, etc. HOLOCYSTITES CYLINDRICuS, HALL. Page 854. FIG. 7. View of a nearly entire individual, showing the central aperture in a depression at the summit. The plates of the lower part are broken off. " 8. A smaller individual, in which the plates have been strongly ridged, preserving a portion of the column. The lower ranges of plates are somewhat obscure, and the dotted lines indicate depressions, which may be sutures or only grooves in the larger plates. APIOcySTITES IMA GO, HALL. Page 358. FIG. 9. Lateral view of the specimen, showing the ovarian aperture on the left-hand side of the figure, and the right pectinated rhomb. (Figure natural size.) CRIAOCYSTITES CHRYSALis, HALL. Page 362. FIG. 10. View of the gibbous side of the specimen. " 11. Lateral view of the same specimen. *This plate accompanied the original paper as Plate I. It is now arranged with the other plates in its order as XII4.