. Bulletin of the British Museum (Natural History), Geology. 314 MID-TERTIARY CYTHERETTINAE Left valve Right valve L H L/H ^W L H L/H Female 1-03 0-58 178 0-31 1-02 0-51 2-00 Male I-I5 0-58 1-98 0-31 I-I4 0-56 2-04 Mean length of larval stages: No. 8, 0-88; no. 7, 074; no. 6, o-6i. Discussion: This differs from C. tenuistriata tenuistriata (Reuss) in the stronger ornamentation. The ridges are much more pronounced, there are no smooth area in the anterior and posterior regions, and the pitting between the ridges is finer than in C. tenuistriata tenuistriata. See also C. tenuipundata and C. mini
. Bulletin of the British Museum (Natural History), Geology. 314 MID-TERTIARY CYTHERETTINAE Left valve Right valve L H L/H ^W L H L/H Female 1-03 0-58 178 0-31 1-02 0-51 2-00 Male I-I5 0-58 1-98 0-31 I-I4 0-56 2-04 Mean length of larval stages: No. 8, 0-88; no. 7, 074; no. 6, o-6i. Discussion: This differs from C. tenuistriata tenuistriata (Reuss) in the stronger ornamentation. The ridges are much more pronounced, there are no smooth area in the anterior and posterior regions, and the pitting between the ridges is finer than in C. tenuistriata tenuistriata. See also C. tenuipundata and C. minipunctata sp. Fig. 20. Cytheretta tenuistviata (Reuss) ornata subsp. nov.; female right valve; x 75. Cytheretta minipunctata sp. nov. (PI. 16, figs 1-3) Derivation of name: Latin—minus, small; punctata, small pits; refers to the ornamentation. Diagnosis : A species of the superspecies C. tenuipundata with six faint ridges and a finely punctate ornamentation. HoLOTYPE: lo 4028, a female left valve. Paratype: Io 4029. Material : 9 valves and carapaces from Cormeilles. Type locality and horizon: Cormeilles-en-Parisis; Bed no. 44 of Albissin, Couches de Sannois superieur. Stratigraphical RANGE AND DISTRIBUTION: Lower marine Sannoisian of the Paris Basin. Description: The dorsal and ventral margins of the left valve are sub-parallel and almost straight; a posterior hinge ear is developed; the anterior margin is obliquely rounded towards ventral; the posterior margin is slightly pointed. In the. 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 British Museum (Natural History). London : BM(NH)
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