These columns sustain an entablature or two, which terminate this stage, and its frieze is enriched with sculpture representing winged sea-monsters and sirens with sacrificial instruments.
Above the first stage rises the second, which is of a round form, with ten fluted columns, which support its circular entablature; the capitals of these columns are similar to those of the first stage, and the frieze is ornamented with foliage delicately sculptured.
A round cupola terminates this building, through which the light shines in on every side, although two male statues in togas occupy the centre of it.
To view the height at which these figures are placed, one would suppose they were safe from the attacks of the mischievous or the curious; nevertheless, they did not escape, for, many years ago, during the night, their heads were taken off, and those that replaced them reflect little credit on the taste or skill of the modern sculptor who executed the task.
On the architrave of the entablature of the first stage, and on the north front, is the following inscription:-- SEX.

L.M.JVLIEI.

C.F.

PARENTIBUS.

SVEIS.
Various are the opinions given by the writers who have noticed this monument as to the cause for which, and person, or persons for whom, it was erected.