I\ T. CLEVE ON SOME FOSSIL MARINE DIATOMS. 171 



T. antediluvianum (Ehr.), Van Heurck. Amphitetras ante- 

 diluviana, Ehr. (1839). 1 have seen only one specimen from the 

 Tegel deposit, and this is not the type form ; the lobes are less 

 obtuse. It more nearly resembles the last described form, from 

 which it differs principally by its coarser cellulation (3 cellules in 

 the *01 mm.) and less produced lobes. Distance between the 

 angles *07 mm. 



Eupodiscus Argus, Ehr. Tripodiscus Argus, Ehb. (1810). E. 

 Argus, W. Sm., Syn. vol. I, 1859. Van Heurck Syn., PI. 117, f. 

 3-6. Several specimens examined, but no difference could be de- 

 tected between them and recent forms. 



Aulacodiscus Oregonensis, Bail. 18G2. A. Oreganus, Ralfs. 

 1861. A. Schm. Atl., PI. 31, f. 4-5. 



A. amoenus, Grev., T.M.S. xii., p. 10, PL 1, f. 3 (1S64). A. 

 Schm. Atl., PI. 41, f. 13. One specimen agreeing very well 

 with A. Schmidt's figure. 



A. Grunowii, 01., n.sp. Valve largo, -1--3 mm. in diameter, with 

 distant rows of granules radiating from the centre, where they arc 

 scattered. Between these are very small puueta ; below the granu- 

 lated surface is a reticulated layer; number of rays 6-10. PI. 12, 

 f. 8, ^f. 



This beautiful species approaches very closely in general ap- 

 pearance to A. Grevilleanus, Norman (T.M.S. xii., p. 10, PI. 1, 

 f. 1, 1864), but the markings on that species show many 

 important differences ; nevertheless, our species has a close 

 affinity with it. A. Grevilleanus was found in the Moron deposit. 



Cerataulus turgidus, Ehr. (1843). Van Heurck Syn., PI. 

 104, f. 1-2. Two small specimens, -05--06 mm. in diameter. 



C. Johnsonianus (Grev.), CI. Biddulphia Johnsoniana, Grew 

 T.M.S. xiv., p. 6, PI. 2, f. 14-15 (1866). A very robust species, 

 •18 mm. in diameter. The puncta of the valve form irregular 

 wavy lines, about *11 in 0.1 mm. (Moron deposit, Greville.) 



Auliscus conjluens, Grun. A. Schm., Probetafel, f. 1 (1874). 

 Atlas, PI. 32, f. 6-8. Several specimens, diameter *1 mm. 



A. ccelatus, Bail. (1853). The specimens from the Tegel agree 

 with Figure 12, PI. 32, in A. Schm. Atl. (from Moron). 



A. Normanianus, Grev. T.M.S. xii., PI. 11, f. 11 (1864). A. 

 Schm. Atl., PI. 32, f. 3, and PI. 67, f. 5. One valve agreeing 

 in every respect with the Moron specimen. 



A. pulvinatus, 01., n.sp. Valve nearly oibicular ; processes 



