KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 26. 



N:() 



Var. amphipleuroides G-run. (1880). — L. 0,13; B. 0,02 mm. Central nodule elongated; median 

 line slightly excentric. Transverse strise 23, longitudinal strise 18 to 19 in 0,01 mm. — Van- 

 heurckia rhomb. var. amphipl. Grun. A. D. p. 47 Pl. III f. 59. 



Fresh water: Finland (E,ussian Lapland, Ladoga)! Mouth of JenLssey! Vancouver Island 

 (Grove Coll.)! 



Var. saxonica Rabh. (1851). — V. lanceolate, with rostrate ends. L. 0,05 to 0,07; B. 0,oi3 

 to 0,02 mm. StrisB fine, 34 to 35 (V. H. Syn.). — Frusfidia saxonica Rabh. (Bac. exc. N:o 42. 

 Fl. E. Alg. p. 227). Grun. Bänka D. Pl. I f. 13. Nav. crassinervia Bréb. in W. Sm. B. D. p. 47 

 Pl. XXXI f. 271 (1853). Grun. Verh. 1860 p. 548 Pl. V f. 12. Donk. B. D. p. 42 Pl. VI f. 12. 

 Vanhetirckia_ crass. Bb.éb. Ann. Soc. phyto. et microgr. de Belgique Vol. I p. 204 (18(38). 



Fresh water: Spitsbergen (Lagerst.), Beeren Eiland (Lagerst.), Sweden! Finland! Germany! 

 Australia (Blne Mountains, Daintree River)! New Zealand! Bengal! 



Var. viridula Bréb. (1849). — Frnstnles in gelatinous tubes. V. elongated, with broad, obtuse 

 ends. L. O, os to 0,ii; B. 0, 015 mm. Strite 28 to 30 in 0, 01 mm. (V. H.). — CoUeton. viridulum 

 Bréb. in Kiitz. Sp. A. p. 105. Vanheurckia virid. Bréb. Ann. Soc. phyt. et micr. de Belgique 

 Vol. I p. 203 (1868). V. H. Syn. p. 112 Pl. XVII f. 3. Frustulia torphacea A. Br. in Rabh. Alg. 

 Sachs. N:o 761 (1858). 



Fresh water: Germany! France (Bréb.). 



4. F, interposita Lewis (1865). — V. linear-elliptical, with broad, rounded ends. L. 0, 12 

 to 0,13; B. 0,02.i to 0,027 mm. Central nodule small, terminal nodules small, approximate to the 

 ends. Transverse strite 20, longitudinal 18 in 0, 01 mm. — Nav. m^er^OÄ/te Lewis Proc. Ac. Philad. 

 1865 Pl. II f. 19. Nav. Martonfii Pant. III Pl. XVII f. 247 (1893)? 



Brackish water: Sierra Leone! Bombay (Grove Coll.)! Savannah Ga.! Oakland, Calif.! South 

 America (Lewis), Hungary, Tallya fossil (Grun.). 



Var. lahuensis Cl. (1883). — Narrow elliptic-lanceolate with obtuse ends. L. O, oss to 0,072; 

 B. 0,0 15 mm. Transverse strise 17; longitudinal 18 to 21 in 0, 01 mm. — Nav. 0'M. var. lah. 

 Cl. Vega p. 496. 



Marine: Labuan! 



Var. incomperta Lewis (1865). — Transverse stria; about 27, longitudinal 22 to 23 in 0, 01 

 mm. — Nav. incomperta Lewis 1. c. f. 20. 



Brackish water: Atlantic coasts of U. States (Lewis). 



Var. Julieui Brun a. Hérib. (1893). — L. 0,o7; B. 0,012 to 0,oi7 mm. Transverse strise 

 about 28, longitudinal 20 in 0,oi mm. — N Jul. Brun a. Hérib. D. d'Auvergne p. 199 Pl. VI f. 8, 9. 



Brackish water: Auvergne, fossil! 



5. F. Lewisiaiia Grev. (1863). — V. linear, with broad, rounded ends. L. 0, 19 to 0,21; 

 B. 0,035 to 0,038 mm. Central nodule small, terminal nodules elongated and linear, at some distance 

 from the ends. Transverse strise parallel in the middle, convergent at the ends, 24 in 0, 01 mm. 

 Longitudinal strise 25 in 0,oi mm. irregularly undulating. — N'av. n. sp. Lewis Proced. A c. Nat. 

 Se. Phil. Pl. II f. 3 (1861). Nav. Lewis. Grev. T. M. S. XI p. 15 Pl. I f . 7 (1863). Vanheurckia 

 Lewisiana Be,éb. Ann. Soc. phytol. et microgr. Belgique Vol. I -p. 202 (1868). 



Brackish water: Sierra Leone! Cameroon! India (Wallich), Batavia! Sendai', Japan, fossil! 

 Brazil (Brun Coll.)! Florida and Georgia (Lewis). 



Stenoneis Cl. N. Gen. 



Valve narrow, with rounded ends. Central and terminal nodules very small. Median line 

 indistinct, bordered by two strong linear silicious ribs. Structure: fine, transverse, strise. Axial 

 area indistinct. 



