BIHANG TILL K. SV. VET.-AKAD. IIANDL. BAND 21. AFD. III. N:0 2. 29 



Kv. 9, 28, 32, Nu. H, 5. 11, 14, 17, l.S, 19, 87, 89, 41, 

 S.-K. 7, 22, 33, Jm. 31, Na. 35, Tj. 42, Cll. 43, 47, Gl. D. 45. 

 — Frequent. 



In Nu. 14 forms occur, tliat make a transition to E. in- 

 cisa var. obtusa CtRUN. 



E. lapponica Grun. in Cleves Ms. n. sp. — Pl. I, 29, 30. 



Valve almost straigbt, linear, slightly contracted at the 

 broad, obtuse ends, 0,0 7 to 0,08 mm. in length, 0,oo8 mm. in 

 breadtb. Striae equidistant, 18— 19 in 0,oi mm. End-nodules 

 at some distance from the margin. 



Kv. 16, 32, Nu. 5, 18, 19, 37, 41. Jm. (i, 31. Km. 10, 30, 

 Na. 35, Tj. 42, (xl. 43, 47. — Frequent. 



Tbis species, common in Lule Lappmark, bas some re- 

 semblance with E. dentieula Rabh. in V. H. XXXIII, 14, 

 but never bas tbe dorsal margin denticulated. It occurs in 

 Cleve & Möller, Diatoms I, 28, 37 under tbe name of E. 

 (denticulata Bréb.) var. glabrata Grun. As it is a smootb, 

 constant form witb tbe ends otberwise sbaped tban tbose of 

 all tbe true E. denticulae I bave seen from Lule Lappmark, 

 and is besides of a mucb larger size tban tbese, I tbink it 

 preferable to make it a new, distinct s])ecies. 



E. dentieula (Bréb.) Rabh., var. borealis A.CL.n.var. — P1.I,33,34. 



Valve 0,0 2.5 to 0,0 4 mm. in lengtb, witb tbe ends almost 

 acutely protracted towards tbe dorsal side. Tbe dorsal margin 

 witb small teetb, 9 to 11 in 0,oi mm. Striae 20inO,oi mm. 



Nu. 3, 18, 27, Kv. 28, Na. 35. — Ratber rare. 



Tbis little denticulate form bas almost tbe same outline 

 as E. Nymanniana Grun. and is perbaps a transitional form 

 to tbis species. I bave not seen any specimens from Lule 

 Lappmark like tbe figure of E. dentieula in V. H. XXXIII, 14. 



E. sueciea A. Cl. n. sp. — Pl. I, 31, 32. 



Valve somewbat arcuate, 0,o2 5 to 0,0 3 mm. in lengtb, 

 0,0 1 mm. in breadtb witb broad, truncate ends and two ratber 

 acute dorsal ridges of a more or less sligbt elevation. Striae 

 14 in 0.0 1 mm., equidistant and of equal lengtb. 



Kv. 1, 28, Nu. 2, 18, Tr. 38. — Ratber rare. 



Tbis species sometimes resembles in outline E. robusta 

 var. Papilio Grun. in V. H. XXXIII, 8, but tbe striation is 

 quite diiferent. It seems to be more akin to E. triodon Ehb., 

 wbicb bas tbe same kind of striation. 



