FRESHWATER ALGÆ FROM TUDDAL IN TELEMARK. 169 



110a. forma intermedia. Boldt: Desm. Grønland. 

 A form of E. pectinatum which agreed well with the forni 

 described by Boldt from Greenland occurred in one sample. 



111. Euastrum verrucoaum. Ehrbg. 



This common species occurred in quantity in a single 

 sample from 4100 feet. Size: long. 87,5 u, lat. 68 u, lat. 

 isthm. 22 a. 



Ilia. var. reductum. Nordst. 



Only in a single sample. 



112. Euastrum insulare. (Wittr.) Roy. 

 Very scarce. 



113. Euastrum crassicolle. Lund. 



This arctic species occurred in a single sample associated 

 with Mougeotia parvula, Zygnema, Micrasterias denticulata, 

 Staurastrum saxonicum, Vanheurckia rhomboides and others. 

 Size: long. 27,5 ^i, lat. 15,5 a. 



114. Euastrum crispulum. (Nordst.) W. & G. S. West. 

 Rare. 



115. Euastrum sublobatum. Breb. 

 Somewhat rare. 



Genus Micrasterias. Ag. 1827. 



116. Micrasterias pinnatifida. (Kiitz.) Ralfs. 

 Only in a single sample. 



117. Micrasterias truncata. (Corda) Breb. 

 Somewhat scarce. Size: long. 112,5 /n, lat. 88 in, lat. 



isthm. 20 /ii. 



118. Micrasterias conferta. Lund. 



This rare species occurred in a single sample. The form was 

 resembling the forma by West (Brit. Desmid. PI. XLIII fig. 9.) 

 being intermediate between the type and the var. hamata. Wolle. 



PI. m, Fig. 5. 



