28 ARKIV FÖR BOTANIK. BAND 14. N:0 9. 



Striae divergent in the middle, convergent at the ends, 8V2 

 —9 in 10 [J.. 



Foss.: Ab. Hindersmossen. 



This form is most closely allied to P. Legumen, though 

 the long and slender valves recall P. stauroptera. It cannot 

 be referred to this species because of the inflations near 

 the ends. I have also found it, in P. T. Cleve's notes, from 

 Lake Rosslängen in Sweden and from Loch Kinnord in Scot- 

 land. 



f. interrupta. — PI. 1, f. 26. 



Striae interrupted in the middle. 

 Together with the preceding variety. 



Pinnularia Legumen Ehb. var. florentina Grun. — A. 

 S. Atl. Tab. 44, f. 8. — Syn. Navicula divergens W. Sm. var. 

 unduiata Hérib. & Perag., Diat. d'Auvergne, Tab. 4, f. 2. 

 — Icon. nost. PI. 1, f. 27. 



Valve almost linear, slightly triundulate, with broad, 

 capitate ends, 80 [j. in length, 16 [j. in breadth. Area less 

 broad than in the preceding variety. 



Foss.: Ab. Hindersmossen {jresh w.). 



Distr. {jresh w.): Italy. 



Seems to graduate to the var. longa. Shorter, typical 

 specimens have a great resemblance to Pinnularia platy- 

 cephala (Ehe.) Cl. from which species they, however, differ 

 by the end-fissures being turned in the same direction. 



Pinnularia divergens W. Sm. var. truncata n. var. — 

 PI. 2, f. 29. — Syii.? Pinnularia Karelica Cl. var. stauronei- 

 formis Hust. A. S. Atl. Tab. 311, f. 13. 



Valve linear-lanceolate, gradually tapering from the middle 

 to the broad, obtuse-truncate ends, very slightly triundulate. 

 Striae, 11 in 10 [J., interrupted in the middle of the valve, 

 where there is a large, rhomboid area. Length 67 }Jl, breadth 

 13 [J- 



Foss.: Ab. Hindersmossen, Ok. Paltamo (fresh iv.). 



This form has much the same outline as Pinnidaria ka- 

 relica Cl., but is a little more coarsely built throughout and 

 has a broader axial area. It comes perhaps as near to P. 

 microstauron as to P. divergens. 



