Vertical episema (neume detail)

The image shows a close-up of a musical staff consisting of three horizontal black lines. On the staff, there is a square note head with a vertical line extending downward from its left side, representing a vertical episema, followed by two diamond-shaped notes descending in pitch. The notation is in black ink on a plain background, characteristic of early Western plainchant manuscripts.

The vertical episema is a specific rhythmic sign used in Gregorian chant notation, particularly in the Solesmes school of interpretation, to indicate a slight elongation or emphasis on a note. This notation is essential for the performance of liturgical music preserved in medieval manuscripts.