Perhaps you are thinking of a different form of poetry? Here are some popular forms with syllable counts:
* Haiku: 5 syllables in the first line, 7 syllables in the second line, 5 syllables in the third line.
* Tanka: 5 syllables in the first line, 7 syllables in the second line, 5 syllables in the third line, 7 syllables in the fourth line, 7 syllables in the fifth line.
If you can provide more information about the poem you are interested in, I may be able to help you further.