The appearance of striation may on this hypothesis be explained as due to the presence of granules in the protoplasm.
In many cases, also, the striation is not confined to the apertures, but spreads over the whole cortical layer.
The blocks are in a measure rounded off, but I have found no striation on them.
In the shape and striation of the valves there is an approach to Cymbella.
The striation of the cones is still present, but is not nearly so clear as it was in the earlier stage.
The present form is smaller but corresponds in puncta and striation.
In the form here figured the striation is as stated by De Toni, but is about 19 at the ends.
It was far enough from the fog-flares for the last least trace of striation to have vanished.
The planation and striation of a stone need not be confined to its under surface.
In the next stage oral movements occur; the striation becomes more marked, and the outer envelope is cast off (c).
1849, from Modern Latin stria "strip, streak," in classical Latin "furrow, channel, flute of a column;" cognate with Dutch striem, Old High German strimo, German strieme "stripe, streak," from PIE root *streig- (see strigil).
striation stri·a·tion (strī-ā'shən)
The state of being striated or having striae.
One of multiple, usually parallel grooves or scratches on a rock surface, produced by abrasion associated with glacial movement, stream flow, a geologic fault, or meteoric impact. See more at glacial striation, shatter cone, slickenside.