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Membranilarnacia densa
Membranilarnacia densa Cookson and Eisenack, 1974
Tax. jr. synonym of Valensiella? clathroderma (Detlandre and Cookson, 1955) Eisenack, 1963, according to Stover and Evitt, 1978.
Holotype: Cookson and Eisenack, 1974, pl.25, fig.19
Age: Late Eocene
Original diagnosis: Cookson and Eisenack, 1974, p. 71
Shell spherical, fairly thick-walled, enveloped by a delicate membrane which is supported by thin supports which stand very close to one another. At the extremity, these supports are divided into short, perpendicularly extending and branched furcation-prongs which blend with the external membrane. The dense arrangement of the supports and therewith of the furcation-prongs can barely be followed individually. One specimen possesses a broad pylome which, when viewed from the top, extends almost up to the margin of the shell.
Number of available specimens, dimensions and origin: 4 specimens.
Type: diameter of the internal spherical body about 34 Ám, diameter of the external envelope about 60 Ám. The total diameters of the remaining specimens lie between about 52 and 58 Ám, the diameters of the internal spherical body lie between about 30 and 38 Ám. All specimens stem from the Browns Creek Clays.
Remarks: Cookson and Eisenack, 1974, p. 71
In the case of the type, the external envelope is slightly polyhedrally deformed; two further specimens are ellipsoidally compressed , but can be easily recognized. The branchings of the supports can best be seen in top-view.
Tax. jr. synonym of Valensiella? clathroderma (Detlandre and Cookson, 1955) Eisenack, 1963, according to Stover and Evitt, 1978.
Holotype: Cookson and Eisenack, 1974, pl.25, fig.19
Age: Late Eocene
Original diagnosis: Cookson and Eisenack, 1974, p. 71
Shell spherical, fairly thick-walled, enveloped by a delicate membrane which is supported by thin supports which stand very close to one another. At the extremity, these supports are divided into short, perpendicularly extending and branched furcation-prongs which blend with the external membrane. The dense arrangement of the supports and therewith of the furcation-prongs can barely be followed individually. One specimen possesses a broad pylome which, when viewed from the top, extends almost up to the margin of the shell.
Number of available specimens, dimensions and origin: 4 specimens.
Type: diameter of the internal spherical body about 34 Ám, diameter of the external envelope about 60 Ám. The total diameters of the remaining specimens lie between about 52 and 58 Ám, the diameters of the internal spherical body lie between about 30 and 38 Ám. All specimens stem from the Browns Creek Clays.
Remarks: Cookson and Eisenack, 1974, p. 71
In the case of the type, the external envelope is slightly polyhedrally deformed; two further specimens are ellipsoidally compressed , but can be easily recognized. The branchings of the supports can best be seen in top-view.