BIHANG TILL K. SV. VET.-AKAD. HANDL. BAND 21. AFD. III. N:0 2. 5 



I. Raphidese. 



Pinnularia Ehb. 



P. nobilis Ehb. — A. S. XLII, 2, XLIII, 1, V. H. V, 2. 



According to Cleve (D. Finl. p. 21) tliis species lias 4,5 

 strife in 0,oi mm., but the Lapponian speeimens as well as 

 tlie fig-ures in A. S. all liave 5,5 to 6 striae in 0,oi mm. 

 Length of the valve 0,2 5 to 0,3 mm. 



Ks. 15, Kv. 26, 32, Tj. 42. — Somewliat rare. 



P. viridis Ehb. — A. S. XLII, 12, 13, 20, 21, Nu. 18. — Rare. 



Var. intermedia Cl. Finl. p. 22. — A. S. XLII, 9, 11. 



StriiB 8 to 9 in 0,oi mm. Valve to 0, 13 mm. in length. 



Kv. 1, 9, 16, 28, 34, Ks. 15, 20, Nu. 2, 5, 17, 19, 37, 41, 

 Jm. 6, 31, Km. 10, 30. Tr. 38, Na. 35, Tj. 42, S.-K. 22, 33, 

 Gl. 43, 47. Gl. D. 45. — Common. 



Var. comuuitata Gr. — A. S. XLV, 35, K. H. V, 6. Striae 

 10 to 11 in 0,01 mm. Length of the valve 0,06 to 0,0 7 mm. 



Ks. 15. — Rather rare. 



Var. rupestris Hantzsch. — A. S. XLV, 38, 40, 41. 



Striae 13 to 14 in 0, 01 mm. Length of the valve usually 

 0.0 4 to 0,0 5 mm.; sometimes np to 0,i mm.; breadth of the valve 

 0,01 mm. In Nu. 18 I have found speeimens measuring 0,1 

 mm. in length, but not diflPering in striation from the forms 

 of normal length. 



Kv. 1, 9, 16, 26, 28, 32, 34, Km. 10, Nu. 2, 3, 5, 11, 14, 

 17, 18, 19, 37, 39, Tr. 38, S.-K. 22, Gl. D. 44, 45, Kk. 48; 

 Ke. 49, Vi. 50. — Frequent. 



P. streptoraphe Cl. Finl. p. 23. — A. S. XL VI, 7. 



The Lapponian speeimens have 7 striae in 0,oi mm. 

 (Cleve gives the number of 5 in 0, 01 mm. for this species in 

 Finl. p. 23). Length of the valve 0, 135 to 0,2 2 mm., breadth 

 0,02 to 0,0 3 mm. 



Kv. 16, 26, 28, 32, Km. 10, Nu. 5, 17, 18, 19, 37, 41, Jm. 6, 

 V. 12, Gl. D. 44, 45. — Frequent. 



The largest speeimens are from Gellivare Dundret; the 

 smaller forms, occuring for instance in Nu. 37, 41, graduate 

 to the following variety. 



