FRESH-WATER DIATOMS FROM ICELAND 



73 



pectinalis minor 



— stricta 



polyglyphis 



prærupta 



— bidens 



— bigibba 



— curta 



— laticeps 



robusta Diad 



tridentula permin 



Triodon 



Veneris 



— obtusiusc 



Fragilaria 



capucina 



— acuminata .. . 



— acuta 



— lanceolata. . . 



— mesolepta . . . 

 construens 



— binodis . . . 



— pumila. . . . 



— semibin. . . . 



— venter 



crotonensis 



intermedia 



lapponica 



mutabilis 



— elliptica. . . . 



— intercedens. . 



— minutiss 



parasitica 



producta . . 



Smitbiana 



undata 



virescens 



— exigua 



Frustulia 



rhomboïdes saxon. . . . 



— leptoceph 



vulgaris 



Universal distribution 



Ear. Af. As. Km. Aast. Grl. J.M. B.E 



U 



X 



X X 



x 

 X x 



X X 



XX X 



X 

 XX X 



XXX X 



X X 



X 



X 



XX X X 



X 

 X 



X X 



X X 



X 

 XX X 



X X 



X 

 X 

 X 



X X 



X 



X X 



X X X X XX 



X X X X 



Distribution in the 



different parts 



of Iceland 



8. S.W. B.W. I. E. 



X 



X X 



X 



X X 



X 

 X X 



X X 



X X 



X X 



■ 

 ■ 



X X 



X X 



X X 

 X 



X X 



X X 



X X 



X X 

 X 



X 



X X 



X X 



X X 



X X 



X X 



X X 



X X 



X 



X X 



