Fig. 63. Cocconeis pediculus , (5 ), cells 15-56n long, 10-37M wide, 

 strongly bent along tbe apical axis; valve with raphe has 

 l6-l8 distinctly punctate striae in lOu; rapheless valve 

 with 15-17 striae in lOu, which are crossed by several widely - 

 spaced, undulating, longitudinal rows of coarse punctae. 

 X 1000. Widely distributed. 



raphe -bearing 

 valve 



raphe less 

 valve 



section through 



transapical 



plane; raphe -bearing 



valve in ventral 



position. 



Notes : 



Fig. 6h. Cocconeis placentula , (5 ), cells ll-70u long, 8-40u wide, 



flat or only slightly curved; raphe -bearing valve with about 

 23 striae in lOu, rapheless valve with about 25 striae in 

 lOu. X 1000. Widely distributed. 



raphe -bearing 

 valve 



rapheless 

 valve 



Notes 



