k2 



l4b Frust\-J.es typically solitary, sometimes forming stellate 

 colonies; ptriae often appearing as costae - SYNEDRA 



Fig. 53. Synedra actinastroides , (5), cells 35-&-U long, 2-k\x 

 wide; striae snort, marginal, Ik in lOu. X 5&0. 



a-c, girdle views 

 d, valve view 



Notes : 



F-''?. 5k. Synedra acus, ( 5 ), cells 100-300u long, 5-6u wide; striae 



12-1*)- in lOu, finer than S. ulna . X 500. Widely distributed. 



valve view, var. angustissima 



' " '" m i . tr^"^rz~^~7~. ""■ . ■iiii :, ! . :i : ii h, i . i .. iiii . i. i .i ., 



"" ' " l , umamX'lJ.ji. J'U^li^' ■■■ • ■■ iiiiiilniii-u:i-i;rn . i— 



valve view 



valve view, var. radians 



Notes : 



