^5 



Fig. 60. Synedra ulna , (5 ), cells 50-350U long, 5-9P wide; striae 

 delicate, distinctly punctate, 8-12 (usually about 10) 

 in lOu; highly variable. X 600. Widely distributed. 



girdle view, S. ulna 



"in miiiniiMuiiMMi nut. miiMiiiMiiiMMii imm 111111 11 UMiiiiiilliimiimiiiiiiiiiil iiiiiimiimiiiiiiimiiiiiiiiiimiiiiiiiiiii iniiiiillllillllllllllimi MI III M I M IIII Iil lliimiiiiiifc 



' """"" "'I'l H III IIlllllllllllllllllllllllll lllllllnillllllllllllUmilllllll IIIIIHIIIIllllllllllllll'llllll l || | ill|llliHMIlliiliiillll l iiiiiii 11.11 mi i 



f.mTTfflllllllllMIIHIIIlllllllinillMHIIIIllMlllllillMlllllllllllllllllllllllllllllllllillllllllllllllllllllllllMllllllllllllllllllllllllllllllll n,-. 



*"""'""'"""""" iiniiiiiHIIIIIIIIIlllillllillllilllilliillltiliiiii i milllliillllli minimi liiiiiiiiiiiimiiinm Jj 



valve views, S. ulna 



valve views 







var. oxyrhynchus 



■giimiiiwiiiiimiii 

 "•"-""uiuiiiiiiiii 



..rflTTTTTTTTTTmTTTrTm — mTTTTTmTTTTTTmTmTth, 

 ^llillllllllHIINiMii iiiiiiiiiiiiiiiiiiiiimpy 



gS5ss» var. oxyrhynchus , 

 form contracta 



var. impressa 



Notes: 



