KONGL. SV. VKT. AKADEMIENS HANDLINGAR. BAND 27. N:0 3. 189 



Var. pnsilla Grun. (1880). — L. 0,oi3 to 0,oi7; B. 0,ou3 to 0, 004 mm. StricE 18 to 23 in 

 0,0 1 mm. — A. D. p. 23. V. H. Syn. Pl. XXVII f. 33, 34. 



Fresh water: Greenland! Norway (Dovre)! 



Var. JacMi Rabh. (1861). — Broader. L. 0,oi5; B. 0,oo45 mm. StritB abont 25 to 20 in 

 0,01 mm. — Achnanthidium JacMi Rabh. Alg. E. N:o 1003. V. H. Syn. Pl. XXVII f. 24. 



Fresh water: Baden (Rabh.)! 



4. A. exilis Kuxz. (1833). — Linear-lanceolate, with ronnded ends. L. 0,oi5 to 0,03; 

 B. 0,008 to 0,009 mm. Upper V. with narrow, axial area slightly dilated at the middle. StrisE 

 parallel, abont 21 in 0,oi mm. Lower V. without axial area and with small and rounded central 

 area. Strite slightly radiate thronghout, in the middle 20, at the ends 27 in 0,oi mm. — Uec. 

 N:o 12 (according to Lägst.). Grun. A. D. p. 22. V. H. Syn. Pl. XXVII f. 16 to 19. A. subhun- 

 garicum GuTw. Materialy p. 29 Pl. I f. 26? 



Fresh water: Belginm (V. H.), Germany! 



5. A. glabrata Grun. (1863). — Linear, with rounded ends. L. 0,oi2 to 0,o46; B. 0,uo68 

 to 0,0 13 mm. Upper V. with 12 to 13 strite in 0,oi mm. Lower V. with 13 to 15 striifi. in 0,oi 

 mm. coarser in the middle than elsewhere. Frustule with broad connecting zone, and rudimentary 

 diaphragms at the ends. — Verh. 1863 p. 146 Pl. IV f. 17. A. D. p. 22. 



Marine: California (Cl. M. D. N:o 120), Pacific Ocean, New Zealand, North and Sonth Ame- 

 merica (Grun.). 



Var. auldandica Grun. (1880). — L. 0,035 to 0,04 mm. Strise 22 to 24 inO,oi mm. Median 

 stripe more distant, 10 to 11 in 0,oi mm. — A. D. p. 22. 



Marine: Aiickland (Grun.). 



Akin to this species is probably the incompletely described and figured Cymhosira minutula 

 Grun. (Verh. 1863 p. 146 Pl. IV f. 27). 



6. A. Biasolettiaiia Kutz. (1844). — Broadly lanceolate, with obtuse, rounded-truncate ends, 

 somewhat gibbous in the middle. L. 0, 055 to 0,o3i; B. 0,oo65 to 0,oo7 mm. Upper V. with narrow 

 linear axial area. Strige parallel, about 25 in O.oi mm. Lower V. without axial area; central 

 area small, ronnded. Stria? 25 in 0,oi mm. slightly radiate in the middle. — Synedra Bias . Kutz. 

 Bac. p. 63 Pl. III f. 22. Achn. Bias. Grun. A. D. p. 22. V. H. Syn. p. 130 Pl. XXVII f. 27, 28. 



Fresh water: Hungary (Grnn.), Belginm (V. H.). 



Forma minnfa Grun. (1880). — L. 0,012 to 0,oi3; B. 0,0045. Strige 24 in 0,oi mm. — 

 A. D. p. 22. 



Fresh water: Triest (Grun.). 



Var. suhlinearis Grun. — Linear, narrowed at the ends. L. 0,014; B. 0, 004 mm. Strife 17 

 to 22 in 0,01 mm. — V. H. T. N:o 11. 



Brackish water: Belgium (V. H. T.). 



7. A. taeniata Grun. (1880). — Frustule scarcely arcuate. V. linear, with rounded ends. 

 L. 0,02 to 0,03; B. 0,oo.T mm. Lower V. without areas. Strife about 24 in 0,oi mm. more distant 

 in the middle and closer towards the ends. — A. B. p. 22 Pl. I f. 5. 



Marine: Sea of Kära (Grun.). 



8. A. Hxidsonis Grun. (1881). — Linear-lanceolate or subelliptical, with broad and obtuse, 

 frequently subrostrate, ends. L. 0,oi.=) to 0,035; B. 0,oo5 to 0,oo8 mm. Upper V. with narrow, 

 linear axial area and parallel strise, 15 to 16 in 0, 01 mm. Lower V. with narrow axial area; 

 small and orbicular or subrhomboidal central area. On each side of the central nodule is a lunate 

 marking. Strise 14 in 0,oi mm., slightly radiate. — V. H. Syn. XXVII f. 25, 26. 



Brackish water: Hudson River! 



