1 92 I. No. 4. THF! PHVTOPLANKTON OF SOME NORWEGIAN LAKES. 



INDEX TO PLATES. 



PI. 



Arthrodesmus Incus var. HuitlVIdtii 



Asplanchna sp I 



Asterionella gracillima 1 



Ceratiiim curvirostre 



— hiriindinella 



— resting-spores 



Cosmarium abbreviatum var. planctonicum 



— contractiim 



— depressum 



Cyclotella comtâ II 



Desmidium Pseudostreptonema 



Dinobryon cylindricum II 



Gompho.sphæria lacustris var. compacta 1 



Gonatozygon pilosum 



Melosira granulata I 



Pediastrum Boryanum I 



Spond_vlosium planum 



Staurastrum brevispinum 



— gracile I 



— jaculiferum 



Tabellaria fenestrata var. asterionelloides 1 



Xanthidium antilopæum II 



— — svar. Hebridarum 



Fig. 

 3 



18 



n 



13-14 



3-5 



16 



