Termination lines for trills
When a trill is to terminate before the end of a note, the note value should be divided to show the exact length of the trill. In addition it may be helpful to terminate the trill line with a notch (as in the second bar in the screenshot) to show that the premature cut-off is indeed intentional (not just sloppy notation).
See Gould "Behind Bars" pp. 136-137.