68 * 



1 bave also it from Dockum Beds Texas, This is from the Sta- 

 ked Plain also, and as I think from the Occidental Sea. hi it I find 

 the foUowing Bacillaria. I do not enumerate ali of the Bacillaria found 

 in this sample only the most common and on which 1 will make 

 some remarks, 



Atnphora uncinalum C. G. E. 



This is no doubt Cocconema uncinatum C. G. E. 1870. Proc. 

 Roy. Acad. Berlin PI. 1 (11) fig. 9. It is Amphora ovaìis C. G. E. 

 with the ends produced, an idle reason for errecting it into a « spe- 

 cies ». 



Achnanthes ventricosa C. G. E. 



This is no doubt Aclinantlies subsessilis C. G. E. with the out 

 line inflated at the centre, another idle reason, just the same as 

 the above, l'or errecting it into a «species». 



Achnanthes subsessilis C. G. E. is first described in the Uifuso- 

 rien^ i838, p. 228, T. 20, f. 3. It must not be confounded with 

 Achnanthes ventricosa F. T. K. 1844, Bac. p. 78, T. 20, f. VII. This 

 is equal to Achnanthes rhomlioides C. G. E. 1844. Proc. Roy. Soc. 

 Berlin p. 121, and Achnanthes ventricosa P. A. C. 1874, pag. 419, 

 and Achnanthes {Stauroneis) infiala P. A. C. and Achnantlies Biaso- 

 letiana? P. A. C. 1880. 



Achnanthes ventricosa F. T. K. is also Achnanthes subsessilis C. 

 G. E. and is figured in the Bacillaria of Kuetzing as living, 



Campylodiscus clypeus C. G. E. 



This is the true Campylodiscus clypeus C. G. E. founded by 

 Ehrenberg in 1840 and found in the «infusorial earth » which is 

 known every where to microscopists at Bilin in Bohemia. It was 

 first named as a Cocconeis clypeus C. G. E. in the Infusorien i833, 

 p. 195. It includes Campylodiscus Castillii C. G. E. Abhand. 1869. Stadt 

 Mexico p. 4Ó, T. I, fig. F, 9, and Campylodiscus Rmnboldtii C. G. 

 E. Abhand. 1869. Stadt Mexico p. 36, T. i, F'ig. E, 3. 



Denticula palea P. A. C. N. 



Navicula oblonga F. T. K. 



This is a common form, and occur in fresh water and bra- 

 ckish (and marine.^). It varies in outlinc very much and is common 

 in the iceberg clays (Glacial period) and ali along the coast in the 

 brackish marsh and mud which is so common on our coast, Atlan- 



