Help with rhyme/poetry?

Question

What is it called when a poem has its first line rhyme with the third line and the second line rhyme with the fourth line.

For example.

Soldiers are citizens of death's grey land,

Drawing no dividend from time's to-morrows.

In the great hour of destiny they stand, 

Each with his feuds, and jealousies, and sorrows.

Answer 1

This is an abab rhyme scheme.  Each end rhyme is denoted by use of the same letter.  

Answer 2

abab rythem. or abab form