What are the potential difference measurements in a series circuit?

When two lamps are in series, both lamps will be dimmer than the single lamp in the parallel circuit as they share the total energy carried by the current, with values that add up to the potential difference across the cell; e.g. potential difference of cell: 8 and potential difference of lamps: 4 and 4, or potential difference of lamps may be: 3 and 5