An In Memoriam stanza is a four-line stanza with an ABBA rhyme scheme, usually written in iambic tetrameter. Tennyson used this pattern throughout In Memoriam A.H.H., and the repeated enclosed rhyme gives the stanza a steady, reflective movement well suited to elegy and meditation.
Example
The evening folds its silver wing
Around the sleeping, watchful hill;
The air grows still, yet not quite still,
And distant bells begin to sing.