COMMENTS ON NAVICULA
Habit
Aquatic diatoms:
Navicula is a minute green diatom found either attached to longer water plants or submerged objects or floating free in isolation They are components of the plankton of sea, lake, pond, so found in freshwater and Marine.
Vegetative Structure
i) Boat shaped:
It is an unicellular diploid bilaterally symmetrical organism enveloped within the cell wall called ‘frustules’. It is boat shaped in value and rectangular in girdle view.
ii)Raphe:
The upper and lower valves are transversed by a longitudinal slit called raphe which is interrupted at the middle central large nodule and polar small nodules of each terminal end.
silica deposition :- its outer wall is impregnated with large quantities of silica.
valve view:- Upper and lower valves one above another with longitudinal slit, raphe.
Girdle view:- Overlapping valves fitting together and girdles Joining point upper most.
