. Bulletin - United States National Museum. Science. EAELY PALEOZOIC BRYOZOA OF THE BALTIC PROVINCES. 79 tions by a slight thickening of the wall. The cell walls are unusually contorted in the macular spaces, which, as shown in figure 20 a, are composed almost entirely of mesopores. Vertical sections show the usual short, immature region with thin walls bending gradually into the thick walled mature zone. Diapliragms are absent in aU of the sections studied. The incrusting zoarium, thick-walled, irregularly rounded zooecia. Fig. 20.—Ceeamopora invenusta. a, tangential section, X20, through a m
. Bulletin - United States National Museum. Science. EAELY PALEOZOIC BRYOZOA OF THE BALTIC PROVINCES. 79 tions by a slight thickening of the wall. The cell walls are unusually contorted in the macular spaces, which, as shown in figure 20 a, are composed almost entirely of mesopores. Vertical sections show the usual short, immature region with thin walls bending gradually into the thick walled mature zone. Diapliragms are absent in aU of the sections studied. The incrusting zoarium, thick-walled, irregularly rounded zooecia. Fig. 20.—Ceeamopora invenusta. a, tangential section, X20, through a macula and neighboe- ING ZOCECIA; 6, tangential section, X20, SHOWING THE lEEEGULAB ZOCECTA AND NUMEEOUS GRANULES OR ACANTHOPOEES; C, VERTICAL SECTION, X20, THEOUGH A ZOARIUM EXHIBITING THE CHARACTERISTIC COMMXINICATION PORES. WESENBERG LIMESTONE (E), WESENBERG, ESTHONIA. with large granular structures, indenting the aperture, gives an aspect to the present form quite different from any other species of the genus. Occurrence.—Not uncommon in the Wesenberg limestone (E) at Wesenberg, Esthonia. Holotype.—C&t. No. 57190, A fragment of the type-specimen and thin sections are in the collec- tions of the British Museum. CERAMOPORA INTERCELLATA, new species. Plate 6, fig. 2; text fig. 21. Externally this new form has less resemblance to Ceramopora than the two species just described; but thin sections bring out the char- acteristic ceramoporoid structure, and especially nunaerous connect- ing mural pores. The type-specimen is a flat, epithecated expansion, consisting of two superposed layers of zooecia, as shown in figure 21a. The ceUuliferous face bears the apertures of large polygonal zooecia, nearly always completely isolated by numerous irregularly polygonal mesopores. The poriferous side is smooth, but exceptionally large. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and a
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