BRITISH DIATOMACE^. 



Sect. II. Valves elliptical, extremities rounded. 



7. Navicula Liber, n. sp. F. V. oblong ; V. elliptical, with rounded 

 extremities; striae delicate, 48 in -001"; colour of dry V. pur- 

 plish, v.v. 



Marine. Coast of Sussex, Sept. 1851, W. 8771. 

 Plate XVI. 133. 



S. Navicula firma, Kiltz. V. elliptical, somewhat attenuated towards 

 the rounded extremities ; striae obscure, 42 in '001", parallel. Length 

 •0025" to -0045". v.v. 

 /3. Extremities suddenly attenuated ; frustule smaller. 



/3. Kiitz. Bacill. xxi. 10. 



Fresh water. Near Lewes, Oct. 1851, TF. Sm. Near Belfast, Dr. Dickie. 

 ft. Lough Mourne and Peterhead Deposits. Can tyre Peat. Marl, Co. Down. 

 (Vermont, U.S., Prof. Williamson. San Fiore, Italy.) 



Plate XVI. 138. 



9. Navicula elliptica, n. sp. V. elliptical; stria distinct, 21 in 

 •001", interrupted towards the central line. Length -0912" to 

 •0032". v.v. 



Marine. Poole Bay, Sept. 1850 ; Seaford, Sussex, Aug. 1851, W. Sm. 



Plate XVII. 152. A'ar, (Sporangial ?) From Poole Bay, 152 a*. Frustule 

 mth endochrome. Frontispiece, fig. CLII. 



10. Navicula ovalis, W. Sm. V. elliptical, occasionally inflated ; 

 striae distinct, 27 in •OOl", interrupted. Length -0012" to ^0020". 

 v.v. 



Navicula elliptica, Kiitz. Bacill. xxx. 55. 



Fresh water. Plumpton, Sussex, April 1852, W. Sm. Guildford, Mr. 

 Capron. Cantyre Peat. Lough Mourne and Peterhead Deposits. Rescobie 

 and Killicrankie, Mr. P. Grant. (Ceylon, Mr. Thwaites, Nov. 1850.) 



Plate XVII. 153. 



11. Navicula minutula, n. sp. V. exactly elliptical; striae faint, 80 

 in -001". Length -0006" to -0011". v.v. 



Fresh water. Near Lewes, Oct. 1852, TV. Sm. 

 Supp. Plate XXXI. 2/4. 



