152 



p. T. CLEVE, SYNOPSIS OF THE NAVICULOID DIATOMS. 



f. 5. FInmdaria JoJmsonii W. Sm. B. D. XIX f. 179 (1S53). Nov. Johns. V. H. Syn. p. 99 

 Snppl. B. f. 28. 



Brackish water: S. coasts England (W. Sra.), Mediterranean Sea! Adriatic! Sumatra! 

 Labuan! Japan (Deby Coll.)! East Cape. North Siberia! Brazil (Deby Coll.)! 



Var. Inlgica V. H. (1885). — V. linear sliglitly gibbous in tlie middle. L. (),(i(; to 0,07; 

 B. OjOoT.'j mm. Stria' 24 in 0,oi mm. — N. John. v. hcbj. V. H. Syn. Suppl. B. f. 29. 



Marine: Belgium! 



Var. fasricidata GtRUN. (1879). — V. linear, not gibbous in the middle. L. 0,os to 0,i2 mm. 

 Strife in the middle 1(5 to 18, at the ends 21 in 0,01 mm. — Grun. in CI. M. D. N:o 178. 



Bi'ackish water: Bengal! 



N. Scopulorum i.s a very characteristic form, which seems not to be veiy nearly allied to 

 any other species but the following. It occurs frequently with niamerous transverse siliceous bars, 

 or in a craticular state, and has then been named (Uimaconeu Frauenfeldii CtRFN. Verh. 18(52 

 p. 421 PL IV f. 2. CI. Lorenzii Grun. 1. c. PL V f. 7. 67. linearw Jan. Rab. Hond. p. (5 PL II 

 f. 2 (18(52). Stictodcsmis australis Grev. Ed. N. Phil. J. XVIII p. 34 PL I f. 1-4 (18(53). 



A^ar. prdonga Brun (1891). — V. very narrow, linear. L. O,.-?.-? to 0,4; B. 0,007 mm. Stri.E 

 in the middle 18, in 0,oi mm., almost parallel, at the ends 20 in 0,oi mm. convergent, punctate, 

 puncta about 27 in 0,oi mm. — Brun D. Esp. n. p. 39 PL XV f. 2. N. fmnelica Castr. Osserv. 

 Cicloph. p. 9 (1889) accord, to De Toni. 



Marine: Gulf of Naples (Brun Coll.)! 



3;'). N. Weissflogii Grun. (1878). — V. rhomboid, with obtuse ends. L. 0,o8 to 0,o8.^i; B. 

 0,oi6 to 0,034 mm. Median line with distant median and terminal pores. Terminal fissures in- 

 distinct. Axial area indistinct.; central area small and elongated. Striae 15 (middle) to 20 (ends) 

 in 0,01 mm., radiate at the ends, punctate, puncta 11 in (),oi mm. forming longitudinal undulating 

 rows. — ISrehissonia':' Weissflogii Grun. in CI. West. Ind. D. p. 7 PL I f. 9. 



Marine: Campeachy Bay! Colon (Deby Coll.)! 



This species is scarcelv a Bi'ebissonia, but in my opinion nearer akin to N. rhondiim, having 

 as the last, the terminal nodules at some distance from the ends, and the strife more distant in 

 the middle. 



36. N. (Libellus) rhoinbica Greg. (1855). — V. rhombic-lanceolate, with subacute ends. 

 L. 0,0.55 to 0,12.5; B. 0,013 to 0,024 mm. Median line with the terminal nodules at some distance 

 from the ends. Terminal fissures indistinct. Axial area indistinct. Central area small, orbicular. 

 StricE 14 (middle) to 17 (ends) in 0,oi mm. nearly parallel on the middle part of the valve, con- 

 vergent in the ends, punctate, puncta 13 in 0,oi mm. forming un- 

 dulating longitudinal rows. Prustules in zonal view quadrate, with com- 

 plex connecting zone. — Greg. M. J. Ill p. 40 PL IV f. 16. T. M. S. 

 IV p. 38 PL V f. I. 



Marine: Coasts of Scotland (Greg.), Greenland! Sumatra! Japan 

 (fossil, Tempere)! 



Var. japonica Brun 1891. — L. 0,i3 to 0,2; B. 0,035 to 0,o5 mm. 

 Striae 13 (middle) to 14 (ends) in 0,oi mm. — Schisonema Japoninon 

 Brun D. Esp. n. p. 43 PL XIV f. 6. 

 Marine: Sendai, Japan, fossil! 



The living frustules of N. rhomhicn have two deeply indented 

 plates along the connecting zone. 



N. rhomhica wiht cell-contents 

 .^)00 times magnified 



37. N. (Schizoiieniii Libellus) Grevillei Ag. (1830). — V. lanceolate-elliptical, with obtu.se 

 ends. L. 0,03 to 0,07; B. 0,015 mm. Median pores distant, terminal pores at some distance from 

 the end. Axial area indistinct, central area small. Strife 18 to 20 in 0,oi mm. (closer, 20 to 27 



